If the 77 didn't look better than the 60 then you had a bad sample of the 77.
I've had the 60mm MM3 for a few years now, and once a year I get to compare scopes at the local bird fair. Opticron has a presence and they let people take the scopes outside to set up and compare side by side.
I had the my 60mm MM3 alongside the 77 MM4 (plus several other scopes like Razor HD 85 and Kowa 553, 773, and 883) and the 77 gave the same quality of view, just brighter and higher mag. It's literally the same scope with a longer/larger objective tube, so assuming equal sample quality the view should be equal other than the inherent advantages of the larger objective + longer focal length. I particularly noticed a difference at high magnification, where the tiny exit pupil and smaller objective make it a bit of a struggle at the top end (35-45x), whereas the 77 is much more comfortable.