Use less fuel and parts wear maybe? Surely, though, the amount of money you'd get from selling the parts wouldn't leave you that far ahead by the time you've had to pay for a retune back to stock etc?
^Sounds a lot like my GF's car. I literally HEARD her tyres were flat as she was reversing out of the garage one morning and suggested she may want to check the pressures...to which she admitted she probably wasn't going to do that as she doesn't know how. Week later she got a flat battery and had the RAC come out so I asked her to get them to pump up the tyres for her (I was away for work this whole time). Have since found out that it hasn't been serviced in a couple of years - so that's on my list of things to get sorted out...
You've missed a lot of history on here with Keith and similar situations involving me or other members. Speaking of... @k31th pics!!!!
Keify is banging an actual human female, apparently. Hasn't provided pics yet though...so can't validate...