I'm sure I'll have mine for quite a while as I've had this conversation a few times....
Me..."I'm gonna get _____ new performance part"
Wife..."you're gonna keep this car for a while, right?"
I tend to get my "performance" oriented vehicles to the point I want them and hang on to them though....so she's pretty confident I'll do the same with this one. However if a 1M came along...all bets are off and I always throw in that disclaimer.