I also have both polished and stacked for maximum length. I think both could be used for higher volumes of oil, at least for the high rev bowlers. The only way I can think to describe the BD reaction would be a strong arc. It doesn't get quit the length that my XD gets, but I don't think there's much out that does. My XD is extremely angular off the break point. If there's a long pattern, say 40+ feet, I usely go with the XD for a game in a half, but once the carrydown is evident out comes the BD. Even though some might stick with the XD, it gets a little squirty for me.
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Fall Arsenal 2009
Terminator
Terminator Rebellion
Buzz Attack
Xtreme Damage (Just Arrived)
Black Diamond
Track Spare Ball