Oz-
Rest easy. The 60's are incredible speakers. Don't let the "what-if's" get to you.... there comes a point of diminishing returns and I think you're already beyond it with the 60s so you're in the clear!
There will always be someone who says "bigger is better" and "more is more" but do you need Marshall-stack-type speakers in your room? Do you need 800-1200 wpc? Dual 15" subs in your room? After awhile, it all gets pointless and people forget about the music or movies that they're supposed to be enjoying.
This isn't a holier-than-others thread... I've thought about one step up in the sub department and replacing my cheap universal disc player with a nice Denon.... but my 60s in my 13' square room are more than enough in terms of power
and delicacy!
You'll be happy when you squash that little nagging voice and I think you made an excellent decision!
