I did some research online already, and have not been able to find the answer, so I bring the question here.

Is the current Gen 2 Palmetto 308 lower compatible with most DPMS 308 uppers? I say most because I understand that there are some cosmetic differences in the shape of the 308 uppers. I happen to have a complete DPMS 308 rifle, and another Aero Precision 308 upper/barrel to assemble, so I wonder if these will fit on the Palmetto lower. I also recognize that it's best to stick with one manufacturer when it comes to the 308 AR, so if it really an issue, I'll just pick up a pair of Aero lowers. The Palmetto price for the 308 components is just too good to pass up.

Any experience on the compatibility of the DPMS upper and Palmetto Gen 2 lower?

There were a lot of hit and miss fitment issues reported here.

At the current prices for their lowers and uppers, I don't know why anyone would not just match the receivers.

You're not doing yourself any favors trying to make different company's receivers work with each other in the imitation AR10 market.