They will hold up ok, but sooner rather than later you will become less than satisfied with the plane's performance. It will be missing that little somthing that you'll just know should be there. Hopefully you'll blame the servos and not the plane. The problem will not be with the plane I assure you. The upside is you'll have all that flying time with the 645's to save up for some better servos[8D] A simple fix.