Gaskets for test pipes

kittens

I have test pipes on my car and threw a check engine light code P2A03. Car was running sluggish and I heard a slight hissing sound. Was determined to be exhaust leak but from where the test pipes are (does that make sense?) was not coming from the catback. I had this fixed and solved the problem for 4 months. But now I am getting code P2A00 which is the same type of code just a different bank.

I need the triangular gaskets in the link

Beluga Racing Bolts & Gaskets Set for 370Z & G37 Test Pipes High Flow De Cat | eBay

but what is the best one to get? This ebay link was provided by the shop but the guy said they were getting too hot. Since it failed again I just have to buy the part and they will throw it on for free. I want to get a different brand I don't think these ebay ones are any good. Does Stillen, Z1 or anyone else make a good one?