Bmenx2

Hi, I'm new to the forum and just recently picked up a 2003 LX with 43k miles and was wondering about the differences between TRD and standard Toyota/Lexus parts.
Specifically the performance differences if any, reliability and overall quality of the parts, etc.
The only mod I currently have is a K&N air filter, but I am considering AT tires, upgraded brakes (pads, rotors, etc?), air intake, headers, exhaust, etc.
The TRD parts I'm considering are front/rear brake pads, air filter, oil filter and anything else that might fit what I'm looking to do. I know the TRD air filter is reusable via cleaning/oiling so it seems to compare to K&N.
Any thoughts/ideas would be greatly appreciated.
Thank you!