If you have places to fly teh Accel i would purchase that. But if your always on the go, i would get the shockflyer. I fly my Tensor(like a shockflyer but a biplane ) everywhere and its great. So the verdict is, if you believe you have enough time to go out to the field to fly the Katana, get that. If you dont, get the shockflyer!
Nealio