I put a 185/65 R14 tire in as a spare. It weighs almost 4 lbs less than the 205/70s on the ground and was cheap. (It's only a spare, I'm not terribly concerned about performance) It takes up a bit less room as well, allowing me to stash the car cover between it and the bulkhead. Because the diameter is smaller, I'll only put it on the front unless the drive is less than 10 miles to a repair station. But in the mean time, I'm saving weght, space, and money.