TKO-600 Shifting Problems-leaks too

[BTTBSS]

My TKO-600 has never wanted to shift quickly from 2nd to 3rd gear. Now I have a leak from the joint between the case and the tail housing. Looking for feedback on Liberty Gear. They offer several upgrades that are supposed to improve shifting and will go through the transmission but I'm looking at between $ 700 and $ 950 depending on what they find. Trans has 12,000 miles on it.

Does anyone have experience dealing with them. Do the mods they offer actually fix the shifting problems with the TKO?

Thanks