Marty,
I have a bunch of MTH Bump and Go's. They work well for almost any application, and have rollers as you have mentioned.
I bought one Lionel trolley. It had sliding "shoes" and I had a tough time keeping it running. On EZ streets with a shallow center rail, I think it would not work as well.
Atlas Industrial Rail trolleys also have rollers. They're a bit longer, and are both Bump and Go AND have an E-unit. Nice design.
Ed
The MTH bump and go WILL NOT go around the D-16 Superstreets track. The wheelbase is just the wrong size it is a little too wide The whhellseels flanges get caught in the curve and ride up.
On the other hand (and possibly confusingly) the larger 2 truck MTH Brill and the MTH PCC cars will go around the D-16 Superstreets track.
Silver Lake - That's a bummer
Eddie - do you have the same experience?
The answers are so opposite, that I want to be sure. I don't doubt either of you, I've just bought enough "dang that's not gonna work" That I'd like to avoid it, if possible 
