First.. you come to a forum with a whole bunch of retired or wanna be retired folks and ask about computer games?
Retired Microsoft guy here.. 26 years with the company and man am I glad Im out of the business.
Anyway, its going to be personal preference, I think. Game developers develop sometimes for specific platforms, some platform manufacturers own the brand (Microsoft Halo and Flight Simulator as a couple examples). So you might want to winnow it down to your one or two most wanted games and decide from there. Or, like my now-grown son does, he owns a couple versions of XBox and PS.
Personally, and Im totally biased here, X-Box does more than just play games. I think its also a media server but Im not in to gaming so I cant do it justice. I guess what I'm getting at is see which units also can offer more besides the gaming as that might also sway your selection. Just a random thought...