To be honest, the first FE791SB I got seemed to have a convergence error, but I have a feeling now that could have been fixed in that it was a fault in the input signal........
I've seen those samsungs, just don't remember them too well so I won't comment. As for the viewsonic- from an earlier discussion I had with GoSharks, it appears the P75F is the same as the Fe791sb.
Hilbert space is a big place.