Jeff,

your pioneer should have no probs with a 4ohm load. that's why you paid a few g's for it!

I think the dq 10's are an older model from dahlquist that I don't kow. I have heard the QX10's, and they're pretty good. Warm vocals, deep bass... but not the transparancy or clarity or highs the M80's have. Nor the neutrality.

the M80's are probably also the least expensive ones, which is always a bonus