The Silver Fox is a slow well behaved kite. Not very twitchy or overly sensitive. I'd check the bridle & make sure all the beads are set for the Turbo. If it's correct, switch it to 3pt and see what you think. When I had one, I mostly used the 3 point but now I don't remember why that was.

If the weight you added was more than the stock weight, that could be it too.
I have flown them both but not back to back. My recollection is that the SF 2.3 is slower than the Hypnotist. They are both pretty fun to fly & trick. One of the biggest differences is the Back flip. The Hypno takes more effort to go back and won't stay on it's back once it's there. The SF will sit in the Turtle position well. The Hypno Flic Flacs super easy though. As long as you have the wind, you can do quite a bit with your SF.