You need to secure the pins on the 'S' or 'Z' forks on the Pro tail. They have been reported to drop out.
I glued the ends with mine using Alridite Metal and it has been working fine for 20 flights. MH recommended CA. Other people have recommended repacing the pins with a nut and bolt. Do a search and decide what you what to do, but do something in case it parts in mid-air.
EDIT: There have also been reports of the tail pulley coming loose on the tail shaft. I ran some Green Loctite around the sides and into the grub screw of mine.