They are both rockers.
I found then at great prices, that's why i am only considering the two (i live in Europe... Romania to be precise
The tech i think is ok with both of them.
Lamar: Rocker, Carbon-steel edges, sintered base, two carbon strips, poplar core, triaxial fiberglass.
SIMS: Rocker, Steel edges, extruded base, one carbon strip, poplar core, biaxial fiberglass.
Regarding the Cranium, i found only one review, and that says that it is above what's to be expected of lamar (actually he was extremely happy with the board). As far as the sims goes, i didn't manage to find any review for the 11/12 model.
The problem is that i'm quite heavy for my height, so i'm not very sure if the sims has a little to much flex for me, so that it would get unstable at higher speed.