Opinions on the Tektro/Oval behind-the-fork brakes

Does anyone have any opinions or scoop regarding how well the Tektro R725/Oval A700 behind-the-fork brakes perform? For some reason I remember something about how that placement behind the fork is a bad idea braking-wise, and perhaps no benefit aero-wise? I’m looking to pimp my bike and these are certainly different, but I hate sucky brakes.

(And if anyone hasn’t figured it out yet, if you find a brake or brake lever and it’s not a funky-looking botique brake like a Zero Gravity or not a Shimano/Campy/Mavic it’s almost always a re-badged Tektro.)

Tektro:

http://www.tektro.com/02products/images/pro/09pro001.gif

Oval:

http://www.ovalconcepts.com/img/dettProdotti/29__main_big.jpg

On some frames those upper arms will clasp the down tube when you brake meaning that you are committed to the line you’re on
.