I have the M80's and an EP350 set at 80hz crossover (because my receiver won't let me play with that, otherwise i'd try 60 and see what i get).

I don't feel anything gets 'wasted' by having towers cutting off at 80hz.

I used to use the M22's and could never get it to settle just right with the bass and i found them slightly too forward, i would get listening fatigue. Not the case with the M80's, and certainly somewhat less with the M60's.

I prefer towers to bookshelves