I fly my Extras with around 35 - 40 % expo. It depends on your max throws.
Just a few months after I started flying rc planes, I got a used Kangke Extra with an OS 46 FX and a tuned pipe. And I found this easy to fly, you just need to make sure not to stall it. It will drop quite a bit before you can recover.
I did spend some time on the simulator, that helped a lot.