I'm using an old Shimano XTR FD 953 as recommended on the Surly site, I got it from Jenson, they also recommend LX
"Traditional swing style
Bottom pull
28.6mm clamp preferred (although a 31.8mm clamp with a 28.6mm reducing shim works just dandy... it just may interfere with your water bottle cage a bit more)
Shimano models LX M571 or XTR M953 work best. The LX are still available for the 2005 model year. The XTR is no longer made in 28.6mm clamp, so a 31.8mm clamp with a shim is necessary"
http://surlybikes.com/blog/spew/spew_12_karate_monkey_and_front_derailleurs/
"Traditional swing style
Bottom pull
28.6mm clamp preferred (although a 31.8mm clamp with a 28.6mm reducing shim works just dandy... it just may interfere with your water bottle cage a bit more)
Shimano models LX M571 or XTR M953 work best. The LX are still available for the 2005 model year. The XTR is no longer made in 28.6mm clamp, so a 31.8mm clamp with a shim is necessary"
http://surlybikes.com/blog/spew/spew_12_karate_monkey_and_front_derailleurs/