I was an installer till I realized I was making more money selling the equipment. I agree that the stock speakers are some of the best that I've seen and heard, but I do not like the stock tweeter. They are too scratchy and harsh at higher frequencies to my ears. The mid range is a quality speaker, well built and will last a long time under abuse I'm sure. As for the JL components, they are one of my least favorite speakers in that price range for the same reason I don't like the stock speakers. The tweeters. JL makes great subs and sub amps, but they don't shine when it comes to mids-and-highs with speakers or their amps. The stock speakers are wonderful, but until you hear a really great set of speakers in those doors, you won't know what you are missing. My MB Quart speakers were a direct replacement for those doors. The fit was perfect. I didn't have to modify the door or build a plate, which is very rare i most new cars. Not saying that all speakers will be that easy, but the MBs fit perfectly, and they have a lot more mid bass than the infinity system.