After owning three SS's (including one Aerocoupe), several Malibus, 4 Regals, 2 Cutlasses, a 442, one GP, a LeMans and a Malibu wagon........I'd say it depends on the styling you like.
I've always thought the Olds and Buicks were built better and weren't as rattle prone as Malibus. All of my Montes developed stress on the cracks doors. The GP's were more likely to have buckets and a console, along with a nice dash layout like the rest of the Pontiacs. I loved my wagon because of the versatility. With the exception of my '78 GP and '78 LeMans, all my other pre-'81 cars had rust issues in the rear frame rails.
We all know the performance platforms were the best because they got all the performance goodies (for the 80's anyway) from the factory.