I have not had any problems with the Rocky ti-100' s or ti-125' s loosing blades. Just screw them down tight and you should be fine. CBM I do all my shooting at 30 yards with a bow putting out 70 ft/lbs of KE. The plywood board changes. Alot depends on the moisture content etc. I have had some 3/4" wood that was not as hard as some of the 1/2" stuff. I use a muzzy 3 blade as a control head to make sure the wood has the right " consistancy" for testing. I would say 1/2" wood most often works out, but the luon plywood is softer and would probably work fine, but I think shooting at 20 yards with most setups would be a good way to go. I shoot at 30 mostly becuase my setup is a bit more than most bowhunters use and the extra 10 yards gives a more reasonable idea of what most can exspect. Arthur Arizona vanes hang on the best, but they shure do get boogerd up, they however don' t come off! The new speed flight vanes are tougher, but at 13 bucks for 50 I don' t use them on my test arrows![]