I really like the deviant fin on my backhand, it seems easier to bottom turn and hit the lip (maybe it is just phsycological but if you believe its true then it is true). My Dominator goes good as both a quad and a deviant thruster setup.
I should get some bigger fins (7's) but I am to lazy/tight to buy some. I might search on ebay and see what happens. Do you think they would make much difference to the G5's?
Do you notice any lack of acceleration when you use the deviant compared to the quad set up?