I have the RM/X's and fully concur that the midrange pot adjustment is VERY important to overall bass response (let alone, of course, the postioning.....mine within 24" of my side and back walls). I now realize, thanks to Eric K (ekovalsky) that the "midrange" pot really handles mids all the way down to mid bass response. The upper bass regions can get too aggressive with the midrange pot even slightly too high, or conversely a bass suckout with them too low. Play a well-recorded (Mapleshade, etc.) cd with good acoustic bass and then make miniscule adjustments to both l and r mid pots. Also realize (and we've documented this many times, sorry to repeat) that the two speakers pot adjustments may not be identically oriented (i.e one may go from 6pm to 3pm, the other from 6:30 to 3:30.....) so make sure you know the start points of each and adjust indentically with that correction.
ted_b
P.S. Oh, and do putty adjustments
P.P.S Oh, and listen to Brian
Ain't flexibility wonderful.