You don't want to mix on them, but.....
I run a television station and needed spot audio monitoring in noisy machine room type environments. The RM-2 is just about perfect for this task.
Plenty of volume, not distorted, and while modest in it's frequency response and linearity, it is easy to hear audio problems like hum, crackles and pops. By the way, that would make a great name for a band.
Anyway, 2 thumbs up "way up" for the Fostex RM-2.