In my opinion the only thing ball reviews do are confuse people, including myself. If you really want to be competitive in this sport, it is best to just drill a bunch of different balls. I'm not talking about averaging 230 on a house shot and winning the doubles pot every week, I'm talking about consistently cashing in scratch tournaments with demanding patterns. Keep the balls that roll good and sell or trade the ones that don't. If you don't have the money to drill a lot of equipment, maybe the demo days can help.
A lot of what makes a ball good is how it matches up to YOU. Not someone with the same rev rate and PAP. Everyone throws the ball differently, everyone targets differently, everyone has different "tools in the bag."
For example, my buddy and I both love the Hy-Roads. We each have several that we throw often. I drilled a Furious and didn't have much success with it. It was OK, but I always had something better. I gave it to him and he has 300 the first game on our scratch league (not a house shot, there might be 3-4 people in the league averaging 200). The C-Sytem is phenomenal for both of us. The point is, you really don't know how good a ball will be for you until you throw it.
There are so many variables that it is impossible to reliably predict what a ball will do for you based on what it does for someone you have never seen bowl. Additionally, I'm not going to even get started on the fact that 90% of the people on this site do not understand ball motion. So why even read their reviews? Find someone who knows what they are talking about (hopefully a pro shop guy that is a competitive bowler and isn't trying to sell you the most expensive ball he wants out of his inventory), someone who frequently sees you bowl, and have them recommend some equipment.
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Two Hands are better than one!!