People forget, the !Q tour and the Pearl have the modified Centripedal Core. Which is low diff and originally designed for lighter weight balls. Meaning, lighter weighted cores and lower diffs for slow speeds. With that, if you are a country hardballer, a stronger drilling is necessary to get a better reaction. I drilled mine relatively strong, !Q Tour Pearl 45x4x35 (p2 hole 1" bit, 3"deep), and it is one of the most skid flip balls in my arsenal. In fact too much flip made me adjust the surface to 3000.
My take, I've drilled a few and seen a few more. Pin under and long pin to PAP's are a bad idea with the pearl. The low rg low diff core needs to get started and the R2S Pearl goes 60 ft so a stronger drill definitely helps. With the solid, some of the same applies, however, understand that the solid is not made to cover 39 boards. This is where the pearl picks up, as the solid is too smooth to recover.