I think in 10 year's time Predator will have a higher "per year sales" market than Diamond.
How did Diamond get the market share over Brunswick? Brunswick fell off the pro tour map, stopped all advertising and sponsorship. Diamond did all of that. Now, Predator is doing more sponsorship, more advertising, and hosting more events than Diamond. Plus, players (both pro and amateur), are loyal to their brand, starting from the 314 shaft in the 90's. I also thing Predator will be more able to meet demand as it grows compared to Daimond.
That's my prediction