I have the PS3 torn down to the drive. I know now I have a KEM-450AAA. The drive was clicking when trying to read, and when it does read it reads very slow. I am guessing the laser is going out, but I have no way of knowing for sure. Now I see all the different drives, lasers, etc. on eBay, and not sure what I should get to fix the problem.
EDIT: Trying cleaning first, didn't see anything on the lens before cleaning nor on the q-tip I used to clean it with. Will come back with the results.