I've put front rollers and classics on a Tubus Tara and Old Man Mountain Sherpa on my 26" wheeled LHT. I've got it set up with the OMM Sherpa and find the handling just fine. On the 700cLHT the handling with the top mount Sherpa wasn't good and went with the Tara low rider. Personally I like the top mount for 26" wheeled LHT, I just don't like how low the bags are to the ground.
http://www.oldmanmountain.com/Pages/...rontRacks.html
I removed the entire quick release lower assembly from the rack and attached it straight onto the top eyelet on the fork with a 1/4" spacer to clear the width of the fork blade at the dropout. While the rack sits narrower than the IRD cantilevers on my LHT I suspect the stock Oryx cantilevers are a smidge narrower. Either way the Ortliebs barely touch the brakes and don't affect braking. I have the panniers adjusted back so they're covering the brakes.