Depends what you're doing with it, tourney or woodball?
I tried Powerball last time out (playing woodball) and it was excellent, I'll be using that from now on. Been using RPS Polar Ice all winter and that is good too.
I've been using for tourneys Draxxus Blaze/Midnight and for training (rec play) been using Draxxus Rainbow all brilliant paint. The Draxxus rainbow is brilliant for rec play but never used it in touneys.