I had the steering stabilizing unit installed on our 2010 mirada this past april and tomorrow (friday) I'm having a new rear trac-bar installed. The steering stabilizer helped tremendously against road wander and crosswinds, especially when an 18 wheeler comes screaming by at 80mph
Our unit is 37 feet nose to tail and 12'10" tall, so every little bit helps. I do not have the trim unit installed because I'm so impressed with the steering improvement that I didn't want to mess with it.
I'll report back after I get the coach back home next week on any improvements or disappointments.