FWIW, I ditched my spare and replaced it with a spare coil, dizzy, spark plugs, leads, small socket / screw driver set, a wheel clamp for when I’m staying overnight at events, a can of puncture puff and an inflator! I figure if it’s good enough for Audi to not have a spare, it’s good enough for the Z!
But in all seriousness, if I was doing a long journey I probably would drop the spare back in but given I only do 1000 miles a year and total blow outs are so rare (I’ve only ever had one in 32 years of driving) I just figured I don’t need a spare as much as I need the space.
Yes I really do clamp my car! I don’t care how uncool it looks - at least it’s gonna make it harder to nick.