I bought a SP3-i7/256 during the holiday season to replace my travel laptop. When I did, it shaved 11 total pounds and about .5" off my carryon weight (I did have sort of a hefty beast of a machine, but charger, etc…).
Thursday night, Jan 15, I returned the SP3. It was the last day to do so for a holiday purchase.
Here’s why I returned it:
 I started a new job this month where I don’t travel up to 100% of the time. The travel load size isn’t nearly as relevant now.
 I got a new MacBook Pro i7-16G RAM/1TB SSD from my new job. I was disallowed from using my SP3 as a work machine, which is what I would have preferred, but that was out of my hands. I’m actually a Linux guy, but between the mac and the PC I don’t really see a difference. The SP3 is well-made (like a Mac) and pretty user-friendly (like a Mac is, assuming you suck with computers), and since I had to run my preferred OS as a VM anyway it doesn’t matter which one.
 I had previously returned/swapped this SP3 back in December because the WiFi just quit working. I saw some other instances of this on the web, but this seems to have been mostly an instance failure. However, I didn’t want my $1600 machine to flake out on me again (assuming I kept it)
 And this is the big one…the screen is just too good. With that degree of density, windows 8.1 did a fantastic job of stuffing a ton of stuff onto my display, but the text of every application was, by default, too small unless I had it plugged into a display (Mini displayport only, btw). This is fixable (usually), but sometime display profiles within applications weren’t so good at resetting font sizes from say 9-10 to 14-18.
If you aren’t over 40 years old (and thus not yet suffering from the inevitable deterioration of sight that seems to plague humans around that time), or if you’re used to squinting or some other scenario where the [exceptionally good] screen is displaying text in font sizes that would be 5-6 pt on a larger display, then this thing is pretty awesome. I had trouble seeing the text in my terminal windows.
I strongly suggest getting a SquareTrade warranty if you buy it from Woot, though, in case the wifi conks out on you (or you break it some other way).
Also you NEED the keyboard cover. It’s basically not really optional, since you’ll want to cover the display when not in use.
In the event that I don’t buy another one of these, I guess I’ll have to sell my docking station, bluetooth surface mouse, and keyboard cover on ebay. All three of those (Microsoft products) are also excellent additions to the SP3, although I might have liked an HDMI port on the dock. I hear the SP4 might use the SP3 accessories, so I may wait around for that and see if I really do need 2 portable computers after all.