I've been thinking about doing one of these for a long time. I know there isn't a lot of space near where the downpipe ends and the rest of the exhaust begins for the electronic part. So I was thinking of just moving it back to just bypass the muffler.
The other concern with the electronic unit is that I've heard a lot of them fail, regardless of the brand, due to heat. Since I mostly want it for at the track, I can just get a cheap manual one that you screw open and closed by hand.
I don't have time to work on exhaust right now, I already have a big todo list and I'm very busy traveling this summer, so I think I'll hold off for now.