I own both the Crux Pearl and also the No Rules Pearl. They are both quite strong but I believe I hit strikes more often with the Crux Pearl and use it far more often. I generally use the Crux Pearl on medium lane conditions to somewhat medium to dryer conditions. On very dry conditions, or oil totally spread out because the lane has been bowled on for many games since last oiling, or very short lane patterns (like 35 feet) the Pitch Blue (urethane) is my choice.
For heavy oil, longer patterns, heavier transitioning into heavy-to-medium oil, a strong reactive solid ball with a good asymmetrical core (esp. for those of us closer to being "strokers" or "tweeners") is a must. I have an Alpha Crux and it has been so far my favorite reactive solid ball, I also have an IQ Tour solid. I tried a use Fight as a ball-down option for reactive solid, and I didn't like it. I have not tried the Sure Lock, but everything I've read suggests it is close to the Alpha Crux but hooks a bit more. I got a good deal on a No Rules solid with a 6-6.5 inch pin and I will be taking that to my PSO tomorrow for drilling, setup, and installation of Vise IT. I also picked up (used) a second Crux Pearl that I will have drilled a bit stronger, and probably bit rougher surface, to use it before my other Crux Pearl.
In order of lane conditions I'm looking at this:
Alpha Crux/No Rules solid
Crux Pearl pin down/1000 abralon sanded
Code Black
Crux Pearl pin up 1500 out of box finish
Pitch Blue
spare ball
