Air compressor and AAA FTW! My spare tire has been gone for a while now and my trunk does not seem to mind.

 

The spare is really only made for a few miles and low speed driving. If you don't go crazy and keep it out of boost there will be little to no drivetrain damage. That being said. I have yet to use mine, but keep it back there just in case. Sometimes its easier to just change things yourself and not have to wait an hour for a tow truck that may or may not damage your car putting it on the truck.

 

I completely understand where you are coming from however I would rather deal with a tow truck than risk it especially considering I am not running the factory tire size. For a while I was driving around with one of my winter rims as a full size spare however opted for the air compressor and AAA alternative.