I don't know that I've ever met a bean masher I didn't like.
I pick them up whenever I see them. I like all the different sized but my favorite one is somewhat big and made from madrone wood. It's from Native Seeds/SEARCH and is incredibly substantial.
I always oil them with food-grade mineral oil but even with care, the cheap ones can split. It's not the end of the world although I wonder if food couldn't get trapped and create some trouble.
I don't know if a wooden bean masher works any better than a metal potato masher but it's a nice tool to pick up when you're traveling.
They work well on guacamole as well.
Before you ask, I don't know where you can get these other types in the states and I don't have them for sale.