I put a pin though mine just in case.I found these and have used them on my last 4 gs planes and have never had one loosen up yet
http://www.espritmodel.com/wing-bolts-wing-nuts-aluminum-us-1-4-20-blue-2.aspx
I simply glue a 1/4-20 nylon wing nut to a 1/4-20 nylon screw and cut the head off the screw. Never had one come loose or break in over 2000 flights.
There is one guy in our club that has these GIANT plastic knobs that has a nut mounted into them. Makes it easy to get them snug and just as easy to remove.
I picked up some of those, heads were a tad small, but they would be super if they had a hex head instead of a flat screwdriver head. I actually just picked up some of these glass filled nylon ones with a flange head that work great, just use a socket head screwdriver, super easy and won't strip easily. http://www.mcmaster.com/#91345a688/=10gqg3y