waterman,
We just finished wet testing, and it appears as though the only 2 major differnces between the 2 are: Geneva is 7.5x 7.5 vs 7x7, Geneva has the hand jets in the Ecstajet seat, and the Tahitian is $500.00 cheaper. Other than that, they are pretty much identical.
My whole family (4 of us) loved the Geneva, and providing we can come together on a price, that is most likely what we will be going with. FYI: Right now, we are at $9500.00 including delivery, setup, chems, cover and lift. I am going to wet test a Catalina in the morning but am pretty set on the Geneva.