I plan on buying the stop tech brake kit for my 10 g37x do I need to change the brake lines or is that optional? If so what are the advantages of upgrading the brake lines? Thanks for the help

 

You'd have to confirm w/ Stoptech, if they use a banjo bolt setup then you'd probably be able to use your stock lines. The advantage of going w/ Stainless would be more protection for the brake line, a slightly firmer pedal, and they look nice.