The M22 and M60 are not entirely kind to pop/R&B and rock recordings, though they excel with classical and jazz music.
For a small room and your musical tastes, consider the M40 a great choice. The M60 may be too big for a small room once the volume is turned up, and the M60's improved bass tightness isn't a major issue with rock and R&B anyway. You will be VERY happy with the bass output of the M40, and treble performance is positively sparkling. I've had the M40s playing for hours on end, and listening fatigue was never an issue (unless I was sick of the music, but that's not the point). It's also an absolute steal if you're thinking of moving to a HT setup down the road.
As for placement, start with an equilateral triangle (or the most reasonable approximation your room will allow) and just experiment with bass-heavy music to find what sounds the best.
