I recently acquired two new racquets, and unfortunately one was about 8g heavier than the other. I got them to the same weight by putting a leather grip on one, which obviously caused them to have different balance points. The one with the leather grip is about 1.5 points head-lighter...
11.61 oz unstrung w/ the overgrip
From what I understand there are only there were only 6.1 releases in in 18x20 with the hyper PJ - the extended length "stretch" model, and the TW exclusive "tour" version...