Evan - I meant to ask you something. In the beginning you were having some problems with the performance or your results with the CTX and then you switched to an open combine mode with ferrous coin after talking with Digger.
Have you tried switching between modes (using the shortcut user button) to see if combine is actually that much better? (Was it more the ferrous coin setting perhaps?) - Not sure what you were running before. I'm early into the investigation and don't have anything to report yet regarding e.g. 50 Co with minimal disc vs. an open Combine.
Thanks
Albert