I recently purchased the AT OC9XSL. I wavered over that and getting the LVB stylus for my Ortofon Black. The massive difference in gain between the Black and the AT proved to be a problem for my Fosgate Signature phono. The hi gain 60db setting induced unacceptable noise that was totally absent with the Black. Granted this was at higher volume levels and didn't seem audible over program material, but for me, part of the enjoyment of owning a full range high efficiency setup is the music 'jumping' out of absolute silent backgrounds. This led me to look at maybe implementing a SUT for a gain boost. Searching for a decent SUT led me to the iFi Zen and I figured why not try it since I could return it hassle free. I'm glad I did. I really like the Fosgate, but I find nothing lacking in the Zen- other than noise in high gain mode. Both the MC lo and MC hi gain setting work well with the OC9XSL. It tracks like a clairvoyant ninja and I've heard nothing suggesting the zen lacking in headroom when the mix gets hot. The new Craft Recordings release of Miles Davis's Relaxin' that everyone seems to be complaining about plays without a hitch and sounds extraordinary.