I think this "what" can be applied on top of "what" is turning into an obsession here on Autopia. The vast majority of the time, when we apply a product "on top" of another product, a lot of the underlying product is being removed.
Most of the so-called sealants here can be applied on top of whatever you want. I’m talking about products like EX, EX-P, WG, UPP, BF, NXT, & the rest of the “I have a carnauba-like shine but last like a mofo because I somehow figured out how to crosslink myself while soaked in oils� gang.
Durability of most of these products is only a few months anyways so it doesn't really matter if the underlying product is causing any bonding issues. Furthermore, the sealants I just listed do not spare much of what it's being applied on anyways (due to *refined* cleaners and/or the nature of their solvents) ...so just apply whatever product tickles your fancy and enjoy your shine without worrying about what’s going on underneath.
The same holds true for waxes. Apply P21S on top of any of the sealants I listed above and you can pretty much kiss them good-bye. The only exception to this rule, IMO, is when Klasse is the underlying sealant.
BTW, mpauly... I agree. Glanz wax is a good product...but it certainly isn't going to 'lock-in' anything.. It'll make quick work of whatever it's applied on top of.