i hAve taken two set out at 200 passes and they measure the same as they went in.....BUT they can let go when you least expect . Im using nitrous, you are running NA? Prob can get one more season on them Also which ones do you have?? I get the best ones with the larger bolts in them, they are pretty beefy and seem to last a while. 1fastmopar puts a ton of passes on his, def more than 200....