Love my MB, would never give it up, possibly my favorite game (and I have owned almost all of the top 20 games over time).
I have owned RIBION and I liked it, in fact I bet I will own it again some day, it has got a lot going on and it is fun. To me it's like asking "do I order steak or hamburger". Um...I like them both very much, I eat them both, but if I had both put in front of me for the same price I think I would pick the steak every time. If money isn't the primary driver...MONSTER BASH! But again, I like the other too. Best of luck to you!