I'd look for a different insurance company seeing how Allstate has free glass in lieu of what your deductable might be. I'm 38, and pay $74/mo. for full coverage, $250 deductible, and glass with the car still valued at $20K. Of course, they would only pay fair market price if it was totaled.
Ever watch a show called Mythbusters? They did that test and found it it does nothing to the engine, other than make it less fuel efficient. If you really want to hurt him, use chlorine, but you didn't hear that from me.
