I have a mentor friend for business where I learn so much and the conversations are generally interesting. Outside of that there are very few who make me even want to talk to them as they are all about their own little worlds and those are very small places which are generally boring. Sounding boards are good to have as they do help you develop, but using the wrong ones can also hinder any progress you might have had.
Having a business mentor is highly valuable for sure. At the company I woe at, they have a mentor program internally too, which seems to work well.
The wrong reference group can be equally harmful. Birds of a feather as they say though...