I've been meaning to write a little bit about my experience with the Surface Pro 3, "the tablet that can replace your laptop," as Microsoft has been claiming. I've had it for just about a month, and I'm really happy with it.
First though, some background about my device usage. As I've said before, I'm not a big app user. Most of what I do in a connected fashion outside of software development happens in web browsers. That said, I have the fabulously inexpensive Dell Venue Pro 8 which can be had for $250 or less most of the time, and I find that Windows 8 is a pretty good tablet operating system. It starts up very fast (especially compared to iOS), and the touch variation of Internet Explorer has finally matured to a point that it's actually pretty good (something I never thought I'd say about IE). It does have most of the usual games available, along with weather and other things. I'm not typical when it comes to apptasticness, so it's probably best to stick to my hardware opinions.
I ran out and bought the original Surface and Surface 2 models, the kind of silly Windows RT tablets. Truth be told, they were totally adequate as tablets, but you had to wonder why they didn't just put x86 processors in them so they could do "real" work as well as be tablets. After all, the keyboard covers have always been their big differentiators, and they came with an RT compiled version of the Office apps. Meanwhile, they also had the Pro models, which had Intel Core processors. They fit into the same height and width of the RT machines, but they were so much thicker that they really failed to be practical as tablets. Between the 16:9 screen ratio and the weight, they were mostly laptops in a slightly awkward proportion.
Then they announced the Surface Pro 3, and that got my attention. Thinner and lighter than the MacBook Air, and it was a full PC inside with Core processors. Much has been written about the pricing structure and the extra cost of the keyboard covers, and I won't rehash that here. My conclusion is that the only way you can really classify the device is as the lightest laptop that exists, and by the way, you can use it as a tablet. After a month of using it, I say it's 85% there. You wouldn't (or shouldn't) buy the thing if you're just wanting to sit around surfing Amazon or Facebook. Even the cheapest Amazon Kindle Fire is good enough for that. The question is more about whether or not you need one device that can do everything. More on that later.
Let me step through the use cases. As a tablet, the screen is a little bigger than the 10" tablets we've all become used to, ranging from the iPad to the Surface models and various Android devices. Because they went to a more traditional 4:3 screen ratio, this one isn't awkward in portrait mode. It's terribly thin, and really light, so it's fairly comfortable to hold. It just borders on being too big, because a little longer or wider and it would feel strange. The pixel density isn't quite to the point of the iPad, but it's pretty close and you can't see any pixels. The screen is really amazing.
All of the Surface models have had that bonus tablet mode, too, because of the kickstand. This one reaches the standard 22 degrees (or whatever it was), but then can adjust to virtually any angle, almost reversed. That seemed excessive, but I've pushed it all the way out when placing it down on a table where I was standing, and also on the floor, with me hanging off the couch (I'm always looking for new ways to be leisurely). The hinge is every bit as solid as the previous models.
As a laptop on a table, running anything ever made for Windows, it's screaming fast. I have the Core i5 model with 8 gigs of RAM and 256 gigs of storage. I think that's the surprising thing when you're using it. Sure, if you've had a MacBook Air, you can't believe how light it is, but this is lighter than that, and it still has a full computer in it (and a far better screen for sure).
The new keyboard covers are a great improvement over the previous generations, but they're not perfect. They now have an extra magnetic strip that sticks to the bottom bezel of the machine, adding a fair bit of stability and a comfortable angle to the keyboard. The key travel is adequate for me, but if you like really deep presses, you'll be disappointed. If you don't have it flat on the table, it's also very loud, and feels just a little squishy. The track pad is actually very nice, but it should have been bigger. I think this is a problem of size, since it is, after all, a cover for the screen. It has that smooth feel of a MacBook, but isn't as tall. It's just so close to being awesome, but falls short. I tend to use a mouse on tables anyway, and if you haven't seen it, there's a Bluetooth contour mouse from Microsoft that's under $25 and it's shockingly great for the price.
Which brings us to the laptop on your, uh, lap use case. Microsoft has gone to great lengths to convince people that they solved the "lapability" problem of the previous models. My assessment is that it's better, but it's not laptop better. That extra stability from the extra magnetic strip does make it far more stable, and the infinitely angled kick stand means you can adjust it as you wish, but there are two issues. The first is that if you're not sitting on a slouchy couch, you might not get it away from you enough to keep the kickstand on your knee(s). The second part is that unless you have excess girth (I have a 34" waist), the corners of the keyboard, where you rest your hands, might not have much support under it, throwing the whole unit into a less stable arrangement. I have found that I can usually settle into a position that's comfortable, but if I move, I have to find it again. This is why I say they're 85% of the way to making this a true laptop replacement.
There's another use case that no other tablet can handle, and that's one for pen input. Microsoft has had a fetish for the stylus for years, but I think this is the first time that it really makes sense. Sure, you can do the text input that has been around for a long time, and it's still pretty great. But now, the pile of awesome is using the pen with OneNote. I've been using it to sketch out user interfaces, workflows and entity relationships, and it's fantastic. Even for scribbling out notes in my terrible handwriting it's solid. You can click the top of the pen and it will wake up the Surface and let you start writing, allowing you to save once you unlock it. That's neat, but I don't use it.
As for "real" work, I've used the Office apps, and it's funny that they look so good in a high DPI, which can't be said about all Windows apps. I've also done quite a bit in Visual Studio, and code has never looked so good outside of my 13" Retina MacBook Pro. You still run into some UI weirdness here and there (SQL Management Studio and various VS plugins aren't right), but it's mostly good. Again, it's so fast. I've only made it warm enough to audibly hear the fans once, and that was running the game Portal for fun (it's one of two games I have on Steam). On days that I go into the office, twice a week, I do a lot of note taking, Lync calls and such, while playing music other times, and I've never killed the battery. I charge it overnight, and by the time I get home, I've still got at least 30% to go. I don't feel like I need to bring my power supply with me. Although if I did, it has a sweet USB connector on it to charge other stuff like my phone.
For play, yes, it's great having the kickstand to watch video. I also popped a 64 gig micro SD card into it, and put all of my music on there. The Xbox Music app used to be a steaming pile of shit, but it's finally relatively stable and pretty solid for the most part (wish I could say the same for the Windows Phone version). HD streams look good and don't tax the CPU.
So do you need one device to rule them all? Absolutely not. Is it pretty cool if you can have that one device? Hell yes. I admit, I didn't need this device, because my MacBook is a huge pile of awesome. But I sold some other stuff, and I love touch interfaces, and this one is particularly pretty. The question is, can this replace your laptop? I think it can, but with the caveat that lap usage might not be great depending on your proportions. I can make it work, but it shouldn't be work to find an optimal position. However, when I'm on the go and using it table top, it's so beyond fantastic because it's just so damn light. Can it replace your tablet? Well, it's too expensive if that's all you want it for, but if you want it to be both your computer and your tablet, then sure. When the cheaper i3 models come out, I think you would definitely want to consider it because you're in iPad-with-more-storage price range.
I realize that I have four screens that fit specific use cases: