Hi Mike and welcome! You are embarking on quite the adventure. This forum is a great tool. My brother and myself are building STI’s. Mine is flying and his is close. I have minimal time in a 7ss (1 hour) so can’t give you the best comparison. I think the guy who is the best info on this is John Moriarty. He had a 7SS and then put a STi wing on. STI wing does better at high DA’s and high altitude. 7SS is quite a bit faster. John is from Idaho so maybe you can connect with him?

We went with the STI because we where not building these planes to be a cross country plane. We wanted the shortest takeoff distances and best climb. Of course when I am in cruise I wish they where faster. STI is a 100mph plane. 7SS is like 20mph faster I think. Both land short.