For me and rock guitar, the old Marshall cabs with Greenbacks in them sound sooooo nice. I think part of the problem between the relationship between hi-fi speakers and pro sound is that in my experience, unless you're PA'ing a system, different speakers definitely sound better with certain instruments. I personally like the Greenbacks with guitars and Peavey Black Widows with bass guitar. I have no idea how they would sound trying to reproduce the full spectrum one might need for hifi though.