OK I have owned Glocks since 1988 when I bought a slightly used G17 from a Friend. When the First G21 were released here in the USA (1991) I got in on a Law Enforcement only Purchase because they were filling these first and I had to Have a 45 Glock! It was the first, and so far out of 6 glocks, the only one I bought new. I do not know how many thousands of rounds I have put through it but it is somewhere near 30,000 rounds down range. I have never taken it completely apart and gave it a through cleaning until today! And Like the Commercial said "It Was So Easy A Caveman Can Do It!" The Guy I bought one of my G30's from would take apart his Glocks every 500 rounds including Magazines. I am of the school if it ain't broke don't fix it. I just believe that the more you take it apart the more you risk losing parts or wearing down parts. Now that I have done it is is really easy and I guess I have 5 more to do (4 actually because one is at my Brothers house). My EDC G30 has had more rounds through it than any of my Glocks (Around 50,000) and I think I need to replace some parts and Springs so I guess that is the next step Oh one more thought in my rambling on this. Only the extractor was really dirty. Nothing else was that dirty. Not the Firing pin or the Springs or any of the trigger group. Now When it comes to Glocks I do not use any oil except if I use break free on the gun. Then it is just the residual of the Break Free. But mostly I clean with Hoppes #9 wipe down and put some rounds down range!