Some import in 5 minutes, some 20. Why?

[gduns - with the Lord]

The best I can figure it depends on the disk. on the 5 minute disks they are most likely disks with no errors, and in really good shape, and without mediaclog. if it has any of the above on it it takes longer. I find that it tries to read the bad tracks and make the best of them I have had some that really take a long time to read, so i copy them to another disk and retry import, then they import fast.