SFB - they are closer to the K1 than the K2. The shape and design are almost 1:1 to the K1. The only difference is that a 10 in the K1 fit me great. With these, the 10 felt long in the toebox so I went 9.5 and they fit perfect, if not maybe a little...you guessed it...snug.
If you were looking at them, I'd say definitely go true to size.
Micky - I don't have very much skate time on them yet but what I do have, I like them. The sole definitely feels thicker than a 'normal' vulc and I can see how some people wouldn't like that. I'll put some hours on them and post back.