I use my m2100 as a 2-shot finisher. For real skilling I use either Breer or Korss depending on prices when I'm buying. Then again, my HG's only 1,700.
I've noticed that while my EP-32 is much faster, missing every other shot (and sometimes 3 in a row
) means I kill the mob at about the same speed with a Breer/Korss and using less ammo and decay. Missing with 6 ammo vs. hitting with 4? Not much of a choice there.