Has anyone had experience with these tires? I am considering getting these over the BFG G/forceT/A KDW's. I have heard the BFGs are noisy and don't want that. TIA

 

Kumho Ecsta Supra 712 are old tires in Ultra High performance summer tire class with the Kumho ecsta SPT. At tirerack.com I don't see them listed in 215/35-18.

The Supras are not quiet. Expect moderate noise.
http://www.tirerack.com/tires/tests/...ay.jsp?ttid=41

For 215/35-18 at tirerack.com in Ultra High Perf Summer tires:
General Exclaim UHP $85 380 treadwear Y speed rated
BF Goodrich g-Force T/A KDW2 $156 300 treadwear Y speed rated
Bridgestone Potenza RE750 $162 340 treadwear W speed rated
BF Goodrich g-Force Sport $136 340 treadwear
Kumho Ecsta SPT $97 320 treadwear Y speed rated
Avon Tech M500 $99 280 treadwear W speed rated

KDW2s are noisey.

For value and good street manners the Kumho Ecsta SPT is worth a hard look. The General Exclaim UHP is probably the more comfortable and affordable but gives up some performance (KDW2 much better on performance).

Contact Alex@tirerack.com if you need more info.