Storage unit neighbor says I park my Mustang wrong, is he right?
Guy in the unit next to mine in Phoenix watched me back my car in last Tuesday and said I was ruining the tires by leaving them flat on concrete for 8 months, but I've always thought jack stands stress the suspension so which is actually worse for long term?
Leaving tires flat on concrete for 8 months is definitely not great, but it's the flat spots you should worry about, not the tires "getting ruined" like your neighbor claims. Jack stands actually take the load off the tires and springs, so they don't stress the suspension at all, the real risk is rusting or bending stuff if you put them in the wrong spots. For 8 months I'd just inflate the tires to max, roll the car a few feet every month or so, and skip the stands unless you're storing it way longer.