My last was a SS RSI in .22LR. Lovely little bugger, but only an average shooter, 3/4” or so with good ammo IIRC. I got the trigger down to an acceptable level and shimmed the bolt, but it only accepted a .002 shim, so was pretty tight. I let it go to finance my 10/22 CSC, which so far shoots at least as well and is more fun. It’s also is easy to swap optics around on with its integrated rail. 77/22s are kind of a pain.
My son has had one of the Varmint/Target model for over 20 years. Good shooter, but not exceptional either with hunting ammo anyway. Heavy too. Still, a nice, full-sized rifle, heirloom material now. I put a Timney sear in that one long ago, and shimmed the bolt a couple years ago. Not sure what effect the shim had, as I haven’t shot it myself. That one has had a Bushnell Trophy 4-12AO on it, a solid bargain RF scope btw, from the beginning.
Good rifles, and generally nice ones too, but I think the current CZ 457 is a bit better, easier to get, and certainly cheaper than the cultish 77/22. My 455 SS, now in walnut, looks nearly as good as the RSI too.
