It really depends on the game. Playing something like Puyo Puyo Tetris on a powerful stationary system is blasphemy over a portable system. I mean do you really need 1400P to play Tetris? I don't think so. Playing Tetris everywhere is a much better option. Some games need the extra power like some cinematic games and best played on a tv. Basically, if a game depends on power than it is best played on a system that uses it. Some games make short play sessions impossible and make portable games unplayable.
So yeah, depends on the game. I think AAA cinematic games are best saved a power system. Everything else portable is better.