I want to take the Fantastic Fan in the cabover, which is an exhaust fan only, put it in the bathroom and replace with a reversible fan in the overhead. I remember a fan I had in my Arctic Fox that...
Shur-Flo Comfort Aire. Infinitely variable speed, infinitely quieter than fantastic fan, reversible, runs with lid closed if desired, great customer service. I have replaced all my Fantastic Fans with the Shur-flo.
(on edit - oh crap! they're discontinued. There may still be some available from dealers tho')