Which wax? They've done away with the "WET" wax, from what I understand. In fact, I think all they sell now is the Nano stuff. If the customer used the WET polish, it looks nice (esp. on SS red.), not a real deep shine, not too long lasting, STAINS TRIM, fills minor marring as opposed to removing it.
The Nano stuff fills marring fairly well, not much longevity, IME. Fairly easy to apply/remove. My pump was defective, so it oozed out the shaft.
I think the WET lasted longer than the Nano. Nano lasts about as long as original GC. (New version is supposed to last longer.) Mothers lasted longer than Nano, at least as long as the WET.
As to getting them at WM, here, at least, you can get both the pump and the spray versions of Nano wax at WM. Not sure about the spray version, as I haven't used it (yet).