no dont listen to him, Mac makes some really nice products although i've never heard of the springs so i wouldnt know about them. People are going to tell you all sorts of crazy stuff on this board, in the end you just gotta make up your own mind about certain things. Some people swear by mac headers and some people hate them just like some people love spec clutches and some people absolutely despise them
But their h-pipes, catbacks and headers are nice, I had a Mac h pipe that fit great, never had a problem...