Absolutely, a waste of money! These cars are heavy sensors and computerize. These new gen Corolla are NOT the old 90s cars where you can do the traditional I/H/E. You will need to invest in aftermarket ECU or piggy-back, plus a tune.
Your Borla muffler is good enough!
Do not waste money on a custom mid-pipe or a fabrication.
If you want REAL performances..bang for the buck.. invest a set summer tires!
go to toyotanation.com they have a thread on mods available, there you will find all the mods for our rollas, and about mid pipe, go to a muffler shop, its cheaper and stainless steel is pricy and it would have the same results