I've grown to expect substandard wheels and tires on any bottom to mid level machine that is typically designed for and marketed toward price-point shoppers. Price-point demographics utilize an entirely different mindset than shoppers who are simply satisfying lust. I've only ever been satisfied with two OEM wheels enough to keep them:
I'm happy with the simplistic yet aesthetically pleasing OEM wheels on my 2013 Rhino Special Edition, but the Dunlop tires were dismal and anemic and I'm much happier with the XTRs.
I'm also really pleased with the OEM 14" wheels that came on my P1000-5D. I like the Bighorns just fine but don't care for how they wear on pavement and will be replacing them as soon as I figure out what I want.
My point in all this is that typically (unless OEM does a great job choosing) I'd rather pay less for a machine and go into it knowing that I'll be upgrading the wheels and tires. I really don't think the P500 sales numbers are due to the OEM wheels/tires; I'm certain that was irrelevant with me. With me it came down to that it lacked a front locker. I can work around any other improvements I'd like to add. I think they kept the 500 basic to appeal more to those who would normally choose a traditional ATV and priced it accordingly.
My youngest two girls are doing just fine on ATVs for now so I'm not in a huge hurry to upgrade them (although they would tell you otherwise) so I'll likely just watch the market for awhile and see what develops. If they (or the aftermarket) releases a front locker at some point this riding season I'll likely pick up two 500s. If they don't I'll likely pick up a pair of late model used Rhinos.
My local dealership in Billings, MT had two 500s, two P1000-5Ds and two P1000-3s in stock but they didn't have one in black (they call it silver) so I ordered and waited.