I changed tires first day. The spare is nice though because if you do damage a rim just use the spare wheel after taking the tire off and buy a cheaper wheel (with lug nut compatibility or get extra lugs) put the tire back on for a spare.
I have done this before several times when I carried oversized tire and rim in a bed mount (always bought 5 wheels and tires) and it worked. I always laugh when I see mall crawler trucks with larger tires and the smaller spare is under the bed. They are about looking cool or so they think. Poor goobers will learn the hard way at some point.