We (ASA - Auxiliary-powered Sailplane Association) always have a towplane at our Parowan event.

Not sure if it has been mentioned yet, but self launch motor gliders often have a release.
So should the motor have some issue and the tow plane is around, you can get a tow so as not to miss out on good conditions.
I wouldn't get a motorglider without a release. Not a bad idea to remain current on aerotow anyways.