The Kumho Ecsta HP4 716 is all about comfort and ride noise. They have unusually good traction for a tire of it's price, but that doesn't mean that they'll hold a candle Falken Ziex ZE-512s or Bridgestone Turanzas.
I have a set of those Kumhos 190/60/15 on my wife's car and they're pretty good. I'm not entirely sure that they warrant all of the rave reviews that they get on Tire Rack (remember, these reviewers just got rid of balding or poor quality OEM tires). But all in all, assuming they get decent tread life (only had them a year), I'd buy them for her Saturn again in a heartbeat. Sorry that I can't comment about treadlife.
Remember that the Supra 712s are considered UHPS (ultra high perf summer, read: soft and sticky compound) while the Ecsta HP4 716s are GTAS (Grand Touring All Season, read: harder compound but softer sidewall for better comfort).
I can't comment on the BFG Traction T/A.