Here's my impressions of the SP3 since having it for a little more then a week.
I have to say that the more I use it, the more I'm really enjoying the computer.
I've not taken it out and about, that will come shortly but using it around the house, its been quite mobile. I'll be taking it into work next week, so I'll get a better assessment of battery life.
I'm finding the the pen to be more useful then I initially thought I would. The screen is gorgeous, pixel density is great, the text is sharp and crisp. Performance is good. I realize I'm not pushing the machine, i.e., not running games. For my needs, it has plenty of power. The touchscreen is great even in using it as a computer (as opposed to a tablet), I find sometimes swiping the screen or scrolling down is better with the screen then the touchpad.
One oddity was trying to get Vmware workstation running, at least able to run a full 64bit os. I had to jump through all sorts of hoops for some reason. Maybe its my inexperience but from googling, I basically had to install Visual Studio from MS, making sure I include the WP phone SDK. This turned on some sort of option to allow 64bit virtualization (weird I know).
I was toying with the idea of throwing OS X in a vmware session, but after looking at the work required, i.e., patching vmware to unlock it, then having a boot loader, etc, etc. I decided against it. I have multiple Macs at home anyways.
In messing around with it, seeing what it could do, I decided to wipe and reinstall. The process was smooth, and worked very efficiently. I have nearly all my apps on the SP3, with the exception of iTunes. I'm still trying to figure out how best to configure and use that, i.e., use a DAS or a NAS to hold my music (I have both).
I'm also looking for a backup app that replaces the same level of functionality as Carbon Copy Cloner. I have a couple on my short list (Macrium Reflect and easeus backup).
Overall, I'm very pleased with the computer, I was worried, after using it for a while, I'd start getting buyers remorse, but that's not the case.
Nothing is perfect and the SP3 does have its flaws, partly because of the platform, and partly design choices, like putting the windows button on the left where you hold the tablet. With windows you need to deal with a gazillion updates.