Well, I just installed new 6.5's, 4x6's, and tweeters in my 2000 Sierra. So far , I love them. Kenwood eXcelon KFC-ST30 Kenwood eXcelon KFC-X462C Kenwood eXcelon KFC-X170 It didn't take too terribly long to install, I just had some minor problems with the amp I was going to use. The amp didn't have a low pass filter, so the door speakers were getting way to much bass. I just switched door and sub amps around and they sound crystal clear.