I really dig the RM22 as well, but the Electradyne is just massive. The RM22 can't sound that big. But the ED can't deliver the goods at such low levels as the RM22. Different Ponys for different rides I guess.
Of the 2 Id rather have Koch MultTone amp..but I do own a Rm22 and it a great amp TOTALLY. And they can be had a good price..not so fpor a Boogie or Koch.
I get ridiculously good guitar sounds on my new recordings.