RE: Velcro for battery packs
Pappas ... I have had no issue using velcro. If you have a fastener on the top and bottom of the battery, it will not move and will hold fast. That means it will not slide on the battery tray and the strap that is going over the top will not slide too, giving you more grip on the battery. Use 2 straps per flight pack and its really secured. Only failure i ever had was when pulling a negative snap and the whole battery tray pulled out. Always remember to reinforce the battery tray if you want to fly hard.