Depends what you want from the wax:
I can only comment about P21S from using its supposedly equivalent "twin" S100 that I bought some time ago from a local Harley-Davidson motorcycle dealership when P21S/S100 was one of those "Flavor-of-the-month" (IE, something new and hyped to use) at that time. Whether they are, indeed, "twins' is a WHOLE different discussion. Needless to say, P21S is an easy wax to use, of the Wax-on-Wax-off (WOWO) that provides a good reflective carnauba "shine/glow" if that is what you want. It much cheaper than hi-end concourse carnauba waxes such as Pinnacle Souveran paste, or even Dodo Supernatural, BUT it has about 85% to 90% of those hi-end carnauba shine, IE, you get what you pay for. The other nice feature of P21S is it wouldn't stain/white streak on vinyl trim like some waxes or sealants do.
The big drawback is it's longevity and protection. It wouldn't last more than 2 months in hot weather and provides minimal protection against bird droppings and bug splatter.
My suggestion for daily drivers is Collinite 476S Double Wax or its marine equivalent (and true twin) 885 Fleetwax, which you may find at any good marine or boat shop over-the-counter, like I did. It's easy to use (WOWO), provided you don't apply it too thick, like many novice/inexperienced do-it-yourselfer's do. You will love the beading of water when washing or when it rains, and it looks pretty reflective. Maybe not show-car/head-turning type shine, but better that many over-the-counter big-box store waxes or sealants that novices use. I like its durability. I get 6 months of good protection, so it makes for a great wax to apply in the (late) fall for winter protection here in the upper Midwest.
The other suggestion is from Autopian All-star, Accumulator, and that is Finish-Kare's 1000P Hi-Temp (the marine equivalent called Hi-Temp Great White). It's a synthetic sealant/carnauba wax blend that has great protection and durability, but you will need to buy it on-line.