Chaos already has M80s which is why I recommended he trade them in. He is not buying them.
And if his subs are ported as he indicated, he should trade those in for sealed particularly since he'll be in a smallish room. Chaos, I lived with the 600v2 for a decade and I deeply regret it. You can read about my nightmare and subsequent discovery of Nirvana in my EP800 review. Go with a 500v4 which is sealed. When you hear it, you will be a changed man.
Socketman's reasoning for large speakers is, by his own admission from his last post, purely a choice of economics. My reasoning for M5HPs is purely for an improved sonic experience.
Also remember this: the M5HPs incorporate many learnings since what I surmise are older, maybe M80v2s that you have. The M5HPs were designed from a preponderance of a modern methodology of family of curves, improved cross-over engineering, all new drivers, improved mid-range baffle and improved cabinet design. All in all, the engineering that went into the M5HPs is far more mature than the engineering that went into the M80v2.
Oh...and the M5HPs were recently reviewed against a floorstander at three times the price and they were similarly good.
And as Craig Chase has said, M5HPs with an Axiom sealed sub, forms a $10,000 speaker-killer system. If you don't know Craig, he is the omniscient grand poobah of audio gear comparisons.
