I got my parallettes after I bruised my forearm, erm, falling off my bike. I was following the Rings One program on rings, but that bruise was rubbing up against the ring strap.

I indeed quickly learned what parallette training can offer. I need to nail my L-sit though before I can start working on the parallette skills that take my core training to the next level - eg. the single arm straddle sit and L-sit thrusts (thrust your legs forward from L-st, then pull them back).