When a site lists melting points for waxes, they are usually referring to "pure" waxes, such as parafin or beeswax, not a car wax. No car wax (even if it says "100% PURE carnauba") is pure wax. They all have some sort of solvent/carrier in it, as pure carnauba is too hard to be useable in its natural state, and most are blended with synthetic ingredients, to give the wax whatever properties the company wants it to have-beading, shine, gloss, slickness, etc., that it wouldn't be able to have if it were "just" pure carnauba.
That said, you might get better durability from a wax than expected. However, it isn't likely to last as long as a "pure polymer" sealant.
General consensus is that wax "lays" on the paint, whereas polymer sealants "bond" to the paint, thus allowing greater longevity (as compared to carnauba waxes).
As GSRstilez said, a sealant base with carnauba topper should yield the "best" look/longevity. I've used just waxes on my car (black) before, and, although I'm up in Canada and don't have the extreme heat that one might have in Arizona, for example, I haven't had any wax (other than #16) bead water longer than 1 month. I have had sealants bead well over 3 months.
If you plan on re-waxing every 3-4 weeks, durability shouldn't be a problem if you want to use a wax.
Hope this helps.