Ok, being now a little fed-up with my vee-brakes, I've finally decided to get some disc. Now despite the merits of hydros, I've got my eye on the Avid mechs, in fact they seem to be selling them pretty cheap now - like US$134 for the pair. But just as I'm about to place my order, what do I see floating on Avid's site? 2 different grades of mechs - 5s and 7s. I always thought that Avid only had one grade of mech discs - does anyone know if this is a new thing? More importantly, anyone tried them and know the diff b/w 7s, 5s and the plain ol' 2003/2004 mechs?