I am almost postitive that Triple Threat coverstock has a higher load of particle in the cover, aside from the obvious that the Threat coverstock is a pearl and the TT coverstock is a compound.
Drilled the same or similar, the TT would grab the lane earlier than the Threat. They both have the same core so you can expect the same fantastic hit out of both of them. I have a Threat and love it, I have been debating a TT myself though. Oh well, good luck!!
--------------------
For a good time call
1-900-TEN-PINS