Problem with small refractors is that if you attach a heavy eyepiece or DSLR to them, then often you cannot moove the scope far enough forward in the rings to keep balance. Standard Vixen bars are around 160mm, so for a small scope you need to get the rings closer together - maybe 80 to 100mm.
It allowed me to balance my rig easily on the EQ6-R
I used the standard rings.
For my Esprit 120, I've moved over to PrimaLuceLab for the rings and bar. The downside is that their rings really only with with their own stuff. They don't use standard hole distances, but it all works well together.
Here's the setup with pictures (losmandy style, not vixen)