My amp will have power to push either speaker so the 4-ohm of the 80s is not an issue.
Never underestimate a 4 ohm load. If you go to pmbuko's Custom Axiom forum search, and type in: "Amp shutdown" you will see the M80's come up.......alot.
Some amps can handle "the load" and only sacrifice some power......others have the "issues" so often posted about.
My point is, that due to the slight bass extension (primarily due to the larger cabinet) and playing louder, many here have been recommending the M80s much more than in the past.
My only concern is that the newer audio/home theatre M80s buyers know what to expect. If they have the right equipment, and have done their research....the M80s are fine....however, I don't think there is anything wrong with admitting 4 ohm speakers are not for everyone.