I'm not sure if I can help since my ball speed is so much higher and probably have a lower track but I have 3 RG Particle Pearl balls, all with symmetrical cores that I enjoy throwing and have had fairly good success with.
RSP: 5" Pin, drilled 4X3 with the pin up. Starts up the earliest of the 3 even with the cover adjusted and with polish. I don't match up very good on short patterns or wood lanes with this ball. But once the ball comes out of the oil and hits the dry, it has a nice strong movement. I had a pretty good shot with this ball on the Shark pattern during the Sport League last summer.
Mystic: 2.5" Pin, drilled 4.5X4 with pin up and btwn fingers. Cover: OOB. I see a nice long look with a strong movement at the breakpoint. I think the movement is the strongest of the 3. I've been able to use this ball on long and short patterns, wood or synthetic lanes. What I noticed with this ball is carry potential. I might be imagining this but I think the strong continuation when the ball gets to the pins just seems to carry alot more strikes than I've experienced with other balls.
Venus: 2.5" Pin, drilled identical to the Mystic. Cover: OOB. I drill this identical to the Mystic because based on the numbers I thought it would be for drier, lighter oil but it's alot stronger than I thought. It seems to pick up sooner than the Mystic but the move isn't as strong so the total boards covered are fairly close, just a different way to getting their. I've adjusted the cover to 4000 with polish but haven't had a chance to try it out yet to see if that change will put the ball where I want/need.
I also have an Odyssey that has taken me a couple drills and cover adjustments to match up to my game at one house so I have to continue to experiment to see if it will be effective at other places.
I also have a Silver Streak Pearl that I haven't used lately because it's more of a go long/flip look for me and I'm starting to pick/drill balls that are more controllable.
Sorry for the rambling but hope it helps out. // Jim
