In reply to:

Do you recognize any distortion on M22ti when volume increase to, let say level 6 or 7 in the range of 0-10?

No distortion heard. Esp with a sub, a lot of the perceived loudness comes from the bass so you don't have to turn it up as loud to feel the same effect. In a smallish room I think M22s + a sub are ideal. They'll give you sound rivaling M60s with less size.