I agree the door speakers aren't that bad, i'm getting ready to take my a-pillars off so i can make mounts for my tweeters from my infinty reference components, but this is just a suggestion for people that want to have a better speaker than stock and not want to do any cutting into the doors or the a-pillar for the new speakers. I mainly put this up there as an option for the tweeters b/c those you can only replace with the stocks unless you want to do some customizing to the trim. And crossovers are nice but if you really want a great sound out of your speakers it's best if you send only the frequencies that speaker is made for too it. In the crossovers you've got the mid speaker there trying to produce really low low's, the mids it was designed for, and some really high high's at the same time, thus creating a lot of distortion. There's nothing wrong with them and they're great for the difference in money. In my system my subs only pick up things below 100kHz and my rears, wich are crossovers, pick up 100khz and up, same with the fronts, but those are componets so it has and external crossover that sends anything below about 180khz to the mid speaker and anything over that to the tweeter, and i can tell you that you'll notice the difference. You can also go louder if you have less distortion
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