That series (221 through 881) are a little older and not as BIG and eye-catching, high-powered, etc... as the G-XXXX and X0X0 series, so they don't get as much attention. HOWEVER, there have been a few threads here from owners talking about how truly good they sound. I remember reading one thread saying that the lowly 221 was a "giant slayer", with a sound way better than what the owner (and another owner who chimed in) ever dreamed it could have. I don't know how the 661 stands, but in general, the sound of that series is pretty nice. Maybe get it cleaned up/fixed up and give it a serious listen (with A/B comparisons with your other receivers) before getting rid of it? If you decide you don't want it, maybe give it to someone who will really treasure it, perhaps an elderly person without a good system, or a younger person who might "catch the vintage bug" from it?