I just bought my first bent (Street Machine GT ('08?) used off Craigslist) last week and so far pretty good. It kind of hurts in the middle of my back but I think that has more to do with my back than the bike.
I bought it strictly for trail use, about 75% of my riding, and will continue to use my DF for street. I'm just not comfortable with the visibility of the bent especially around here (Pittsburgh) where drivers can barely deal with DFs. I think that's the reason you see them on trails and not streets. IMO.