I'm in the same position, very little overhead space. Check out GarageJournal.com, there are a few threads about the Quickjack...
http://www.garagejournal.com/forum/s...d.php?t=253824
http://www.garagejournal.com/forum/s...d.php?t=250314
http://www.garagejournal.com/forum/s...d.php?t=217318
http://www.garagejournal.com/forum/s...d.php?t=228823
http://www.garagejournal.com/forum/s...d.php?t=239561
One plus is it's portable, choice of 120 volt AC or 12 volt DC. With the 12 volt you could use the batter from the car you are working on.
However, I don't think it's a drive on system. You have to place it under the car, not drive over it. This is what is making me pause. My garage is so small I would really like something that I can just leave in place.
There are also threads on scissor lifts installed in garage floors.
Post what you end up with.
Good luck!