I typed JT Sprockets in BA.com "search" and got 340 hits. Not wanting to read all 340, I did see a few members who had ordered from JT. Maybe they'll chime in. There are several discussions pertaining to the ratios (16*17*18*19T). The one constant is to stay with steel - no aluminum.
As for me, I run a 19/42 in Florida and switch back to 17/42 when I'm in the North Carolina mountains.
