If I could walk into a showroom tomorrow and buy either a brand new AE86 or GT86, I wouldn't even give the GT86 a second glance. IMO the 16v 4A-GE is one of the best engines ever made and if I wanted a car with a Subaru engine in it, I'd buy a Subaru. Obviously a brand new AE86 isn't an option so as a daily driver the GT86 would make more sense, but even still I'd rather spend good money on a tidy original AE86 to use as a weekend toy and drive something cheap and boring everyday.
I've driven a few GT86's although not out on the open road and I'll probably sound like an old fart saying so, but they just don't make them like they used to.