Its funny hearin people sayin Appys arent god for barrels considering the Nez Perce Native Americans bred them for their speed and agility...
"The Nez Perce became excellent horsemen as well as the only Native Americans known to selectively breed their horses. The horses were bred to be strong, fast, sure footed, and intelligent mounts... were used to hunt buffalo and deer.".. all traits of a good barrel horse( except the hunting the buffs...)!
I say go for it!