Issues with wheel studs

Alto101

I have a 2017 Q60 that is well setup for HPDE track days. I run a dedicated set of wheels and tires (Titan 7 wheels with Hankook RS-4 tires), wheel mate SR48 lugs nuts and have had a great time doing HPDE at VIR. The shop there stores my track wheels and we swap them so I don't have to drive them to and from the track. They are very careful in starting the lugs by hand and I trust them.

I have now had 4 wheel studs that needed to be replaced. They spin and I can't remove the lug nuts. This happened again today when I was taking off the summer wheels and putting on my set for winter. The wheel studs I am using are the Z1 extended studs so I assumed they were decent quality.

Do I need better quality studs to withstand the track abuse or do you think the wheel studs could have been installed improperly? I am 99% sure that it isn't being caused by switching the wheels around as everyone who touches my car is careful.