Buy one used, you'll sell it in a few hours if it doesn't work for you in your room - only you can tell.
That's the problem with trying to find a used RM10--they vanish before I can even see them. Happened just yesterday. Didn't even get to see the price.
I think Richard recommends 40 watts min with the 2s
He does and that's what prompted my concern. But Trelja's observations pushes me over the edge. The smallest Atma-sphere S-30 would probably do well as well? But those seem to be even rarer than the RM10's.
To the original poster: there's an upgraded RM200 for sale right now (no relation to me) at 40 watts. Too spendy for me, but might work for you.