I can't comment on boot manager functionality unfortunately considering I don't use it. But everything I use sure works.
You should try it out, it's pretty cool (unless, like I mentioned, you're trying out JB, it works well with ICS). I keep CM9 as my main Rom, but boot in to AOKP via Boot Manager every now and then, completely skips the whole recovery process of backing up, wiping, flashing, playing around with your secondary Rom, then returning by wiping, restoring...
Free version and Pro version