I personally haven't or wouldn't apply a wax or sealant with the PC. I also do the sealant or wax by hand with a terry app or a microfiber applicator. I guess you could apply a sealant or liquid wax with the PC and a finishing pad if you put it on 1-2. It could speed things up slightly but I will stick with doing it by hand. Doesn't take that long anyways plus that's the time when you get to put down the PC or rotary and take a break! lol. Just my $0.02
Recently I switched to a PC for applying sealants and waxes and wish I had done so a long time ago. I use a LC CCS Blue pad and do my entire car in less than 10 minutes, and get a uniformly thin application.
I prime the pad with 1 spray of XMT Pad Conditioner or Z6, then afterwords I clean the pad by spraying a number of times with XMT Pad Cleaner then rinsing with water. Depending on which sealant or wax I'm using I'll hold off cleaning the pad until after the 2nd application.
I use the PC for applying sealants and liquid waxs. much faster and more thorough, seems to last longer as well, I guess because it works the product more fully into the paint. I put paste waxes on by hand, and buff off manually, I dont get on with the PC for removing product, and if it doesnt come off easily I dont use it!!!