same here kind of. my medium oil ball is a 14lb brunswick power groove, which is only a mid level ball, but it's so consitant i bowl really well with it. but if i the carry down becomes a problem and i start coming in shallow it gets ugly sometimes when i come in too shallow or too high. my 16lb ebonite big time just makes pins explode even on a bad ball. but my big time has a lot more of an angular(sp?) shape, so it seems like this could be where some of the power comes from.
it does seem like my 16 gets a lot more pin action on a bad ball than my 14 on a bad ball though.