I have experience with both.
C much more simple to drive. (not often as much tow power)
A harder to drive but can usually tow a toad.
Both self contained. A typically will have bigger tanks and better for boondocking.
Travel Trailer you typically tow with a get into town vehicle, but not as self contained.
Best one of the bunch IMHO is C's for 1 week camping trips, A's for voyages across the country where you want a toad.
I also think small fiberglass TT's are great for 60 somethings just starting retirement that want to tour the country and have decent health to setup. (Think Casita)
A's are better for easier setup, as are C's.