The airframe will stand up to the 75 if the operator is somewhat careful of the position of the left stick. The same power that can help you get out of a situation in a hurry can also get you into one at an even greater speed. I would imagine you would be able to train at 1/4 to 1/3 throttle, probably 1/2 throttle to take off. I would advise caution, but the airframe will handle it. I have tortured my Alpha's, they last pretty well. My oldest one is 5 or 6 years old, and still gets flown a lot, especially when the wind makes flying my nicer planes more "iffy". I converted one to a taildragger. It's more of a sport plane than trainer, kind of a cross between a 4star and trainer..

Good luck.