Your likely to get as many opinions as there are people as to if the M80s will be a significant improvement over the M22s in a 5/7.1 system. I have both the M22s and M80s and found that in the smaller room I just moved from I don’t think the M80s+sub are a big enough improvement over the M22s+sub to justify the cost. I haven’t done any A/B testing in my larger room but from what listening I have done I think the M80s are worth the extra money, but that’s just a first impression. They just seem to have more presence.
If you are willing to risk eating a $60.00 shipping charge the best way to find out is to order them and have a listen for yourself. That’s how I ended up with the M22s. I tested them against QS8s for rear speakers and even though the QS8s one that starting position I just couldn’t sent the M22s back because I thought that they just sounded to good and knew I would find a use for them.
So if there isn’t anything you can think of that might give you more bang-for-your-buck than a pair of M80s then I say at least try them out.
Cheers,
Dean
