Wow! That's like saying "What motor vehicle should I buy?" I dunno. Civic, Prius, Silverado, Ferrari, Rolls Royce Wraith, Ford Fusion, Gold Wing, Harley Davidson?

IOW, it depends on what you want your pool for, both in terms of function and appearance. AG pools range from 10' diameter Intex-type donuts to 20'x40' FantaSea, Kayaks and Splash pools. Even some IG pools have steel frames and bodies that allow them to be erected as AG pools.