I have tex in my 450SL and it looks new; spent a lotta $$ to replace the leather in the SD after the original covers fell to pieces trying to replace worn out crappo horsehair pads. Now that it's done, I would have to say the leather is more comfortable to sit on (esp in hot AL summers), but the low maintenance aspect of tex would make me go for it given the option. Maybe it's because my tex is navy and looks "richer" than lighter colors, but it looks almost as good as my new leather. I think for the convertible tex is the ONLY way to go.....just put a couple of towels in the trunk so your legs don't burn to the seat in August....
Clean up requires only a damp towel.
On a side note, does anybody treat their tex? I have used Prestine (sp?) clean from Leatherique to clean and condition periodically. It doesn't leave any film or slippery sheen, but it's kind of expensive. Leather conditioners seem to leave a film.