TEX is crap, read my complaints in the TEK thread. The client source doesn't compile so you have to use a binary you don't have the source for. ZET is better than TEK but ZET was a massive insta-mine so it has no credibility, hence little price support. All the newer sha256 alt-coins are crap so far. I am still looking for one. Only TRC and PPC are viable atm. both have reasonably high difficultly compared to the other sha256 alts.