Just put in all new GM fasteners when you replace the stock stuff with the BMR stuff, or upgrade as you see fit. Going forward, you only have to replace 6 TTY bolts when you do an alignment if you go the GM bolt route. They are not expensive, and the alignment holds tight. I have all service work done at the dealer, so the bolt replacement is built into the price of the alignment. This is for street use.
I would take the TTY stuff seriously. What you upgrade to is up to you, but I would not re-use any TTY bolt that has been torqued to its yield point.