Flaw in my Plan

So, I stick mulishly to the 1911.  And the bad guys manage to legislatively keep a mag size restriction and get it past SCOTUS.  Time marches on.  And, for some reason, I want to switch to something else.

Well, damn, all the magazines are gimped in the future.  Would that I had the forethought to buy magazines back in 2014 to insure against this eventuality. 

Yeah, right.  What mags would I buy on spec now to prepare for 20 years from now?  I don't know what model of pistol I'd prefer.  And what mags used 20 years ago would work today?   Say, if I bought a mess before the Brady Ban came around.

Glock, maybe.  There was no M&P in the world.  XDs were something else and I bet the mags aren't usuable.  But it's a fools errand.  Unless... I buy a half dozen now and look to trade later?  Meh.  It's too complicated to get in a twist over.