I got my 180mm uncoated windcutters from John Wilkies and my friend Keiya got his 180mm uncoated windies from Extreme. P900 petot each.
I use these with BB7 calipers and Speed Dial SL levers. Compared to my 185mm Avid Polygon rotors, these are about 50g lighter (but its not really that noticable while pedaling). Braking power is lessened a bit because well, the contact with the brake pads is less and my calipers are set for the 185mm avid rotors. Still, these look much more bling which is the more important thing hehehe.
I'm using a 160 mm windcutter on my rear wheel with 08 xt hydros. I just noticed that the orig round shimano rotor was "grabbier" while the windcutter was easier to modulate, but needed a stronger pull on the lever to lock your wheel, probably due to less surface area touching the pads. Overall, the difference in feel/performance is practically inconsequential, esp. on a rear wheel. But the windcutter looks friggin cooool! Plus, you can use the rotor to cut things if you dont have a knife, like old tubes, gauze tape, etc.
Does the rider choose the trail, or the trail the rider?