I haven't actually tried it, but I understand that if you layer a coat of carnauba over a polymer wax, it will give the deep, wet look of carnauba. I would imagine that the depth will dissipate with the carnauba as it wears off. Might as well stick with the carnauba if looks are what your after.
Meguiar's Gold Class is a polymer as well, so I really don't think that it would improve the looks dramatically.