I've read about some "hybrid" panels that use both so the panel can work decently in both shade/overcast conditions as well as direct sun. However, I forgot who was making these. If they lived to the hype, for the precious space on the top of a RV, they would be the best tool for the job.
However, if one had a portable frame with panels on it, then the need to maximize every square inch is less important.
Same with a MPPT controller. For the limited panel space on a roof, one needs every single possible watt, so a MPPT controller goes without saying. For a frame or array where space isn't as important, a PWM controller might suffice because one can add panels fairly easily.