The FB-85 has been out a couple years now and I hear that the MB-85 is going into full production Jan 1, 2013. I think they have the electrical stuff worked out on the FB-85. Most of what I have heard is pretty good. I saw in a magazine last week that Rosco/ Blawknox has put out a new broom called the FB-90. It looks like a Challenger, I think, with a new name on it.
The Pros and Cons I have heard is that it takes a couple days for an operator to get use to the bells and whistles. The Broom head opens, closes, and side shifts. Operators can change brooms in just a few minutes without having to get a mechanics help. There are no issues with the axles. The Brakes are sealed and the ring gears aren't breaking.
It has an adjustable float system. The Down pressure can be adjusted from inside the cab. Some people like this because they can clean the asphalt in "one" pass. Other supers have told me that the operators just wear the cores out to fast if you give them control of the down pressure.
And you right millinman......everybody knows Roadtec Service.