The Minima seems to have the exact same range of peripheral vision as the Sporasub Samurai (at least on my face). Unfortunately, the minima is a little restricted in its vertical field of view. I find myself having to move my head a lot if I'm looking for something and it's a little annoying. That and the oversized nose pocket are my only two beefs.
I tried the Samurai and preferred it for shallow depths due to it's stiffer skirt. However, the minima's soft skirt really seems to pay off at depth -- the mask just squishes inward w/o building much of a pressure differential w/ the surrounding water (i.e. squeezing your eyeballs out) -- and the reduced volume leaves that much less to equalize.
As far as the minima's sucky, flimsy, overly-long strap goes, I just got a beefy silicone replacement strap and rammed it in there -- works fine. In fact, the heavier strap never "creeps" and the extra tension probably reduces the volume a bit. The original strap is now my spare in case the main strap goes (doubtful!).
All in all a lucky purchase. The more I read, the happier I am that I bought one.