The benefit of the CRC checking from my perspective was that you can just drop any tunes in the soup and not have to worry if you've already uploaded them before.

To be able to identify a rerip, you really need a hash function that is designed for music (like a soundprint). Right now we're looking strictly at file contents.

So say you drop a tune on and the hashes match (i.e. you already have this tune on your Empeg). Right now it skips that file as a duplicate -- are you saying you want the old tune to be removed and the new one to take it's place instead?