I guess we're off the front disc/fork rails now. I've been running 30mm deep X 19mm wide Deep-V rims on my 36H hubs. Probably going to go to 28mm deep X 24mm wide Kinlin XC279 rims, which are available in 36H, when I wear out my next Deep-V sometime this winter. The Kinlins should have just a little more exposed rim for cooling than my current rims. I think the area exposed for cooling is the critical thing for rim braking.