I haven't considered the A/C system to be a common problem on the Rams, I've owned 5 of them and haven't had any problems. They are weak on the engineering side though, seem to struggle to keep things cool when it gets really hot. My '03 was the worst in that category.
AC would be nice today. Had to drive around Tri-Cities with it being 96F in my backup rig which has no AC. Starter is dead on the '96 and the '98 is loaned out, so I guess you could say the problem with my AC is the dead starter :-laf