Two things so far bother me.
1) the pen loop isn't as bad as i feared, but it still looks cheesy.
2) in tablet mode you swing the cover around the back, but then when you hold it your fingers hit all the keys. Yes, the keyboard is disabled so it's not actually causing a problem, but it still feels weird. Of course the solution is to pop it off, twist it around and voila. So not a big deal at all.
*Just thought of one more. And this really isn't MS or the SP3's fault but:
Why does Chrome look like garbage on the SP3? Is it the high resolution combined with the scaled desktop? Because IE11 looks gorgeous whereas reading text on a Chrome webpage looks like it's smeared with vasoline. Even their icons on the task bar are little pixelated messes. I don't have anything against IE11, but all my bookmarks are synced through Chrome (including work/home/phone) and i don't want to change. I would be very appreciative if Google fixes this soon.