I'm not that familiar with SRAM rear mechs, except I know that some have a 1:1 pull ratio and some are 2:1 (like Shimano). I think this is marked on the mech, so if it's a 1:1 type you'll have to stick to a SRAM shifter or change the rear mech.
That's as much as I know, yessir!
Edit * - it seems that the ESP mechs are 1:1 pull ratio, so it'll have to be a SRAM shifter.