sv_consistency 1 will allow all custom models unless the files are huge, 2 will drop them off server, of course 0 disables check.
Lots of people use custom models here, I like to roll default =P
Some of these SMAC auto bans are default level, like r_drawdecals 1 (bushes, posters on walls, ect). I would hope SMAC would be forcing the option to 1 and not banning because of it, this removes lots of hiding spots if disabled. Would be nice to take the time and test on the server on a per convar basis when people have the time.