I agree that your Yammie has enough power to push your M60's especially considering the smallish room size; however, if you want a cleaner more open and unconfined sound that plagues all but the absolute best receivers, then get an external amp. Since I actually own an M200, I can honestly say that it is an excellent little amp. I use one for my center channel speaker and plan on replacing the B&K Reference 2220 that I use to drive my mains with two more M200's soon. Give the M200's a shot and be sure to let us know how it turns out.

Mini Rock's Lounge.com