I tend to be a variable freak and don't have any that are less than 3-9X, but have tried some 2-7x and they're a bit shorter/lighter.
Regarding mounts, the weaver dual-strap rings are junk!! I've had threads stripped with only moderate torque. They are second only to Tasco rings for stripping threads.
The standard Weaver Top Mounts are much more substantial. I like the four-screw rings much better than the older-designed, 2-screw ones. Filing the bumps off inside the rings will eliminate scope dents.
The Weaver Top Mount base is much stronger and made better than the one supplied by Ruger.