What brand or make of products are most comfortable for full upper and lower dentures?

Doesn't matter: Most, if not all, of the comfort and function of a denture comes not from the materials or brands used...It's from how well they fit. Find a dentist in your area who is experienced in full denture treatment and go with them, even if it costs a little more.

Best quality: Laboratories use many different types / brands of teeth and acrylics. My favorite (and among the most expensive) are portrait teeth by dentsply and lucitone 199 acrylic for the denture base. My laboratory custom colors (tints) the pink base to make it more natural and lifilike. The best treatment you will find for dentures is with a prosthodontist. The difference is appreciable. Good luck.