Thanks Sergio and Ken..
I don't really compete, except for fun, but I like a good blast at max speed with power. What I'm into is how far up the wind scale I can comfortable go on my formula before I switch to something smaller, in this case my S-type 126. Yesterday I tried my new set up against a friend on "normal" formula gear. I did blast pass him, but with a surprisingly small margin, though the "feeling" of speed seemed huge (I would have survived longer than him as my stand was more relaxed). On my ST 126, I had no problem passing him in comfort on a deep reach, but my pointing was horrible...
Maybe I should go for a big iSonic to get both the feeling and the real speed (and some pointing). Does any of you have any experience with bigger iSonics compared to formulas, speedwise, when not going deep or high?