Dear Mike:
I'm guessing by reading the responces you received that by now you may have already decided to do the Magnum upgrade. I thought I'd throw my $.02 in, in case you're still on the fence. I suspect that if you go for the upgrade, when you get your pre-amp back you'll be wondering why anybody would buy a standard version when the Magnum is only another $250! The differences are not subtle. The Magnum adds more weight and clarity to the bass. Images come from a quiter, blacker background which lends to greater apparent detail. In addition, the unit IS more detailed, less vailed and has greater snap. It is also faster and more dynamic, more liquid through the midrange and exhibits better decay. Overall it is more lively and more engaging. If you really want to get your sox knocked off, put it on a set of Walker Audio Valid Points with a couple of the sets lead discs on top. This will magnify the improvements 2 or 3 fold! If you have any specific questions, please don't hesitate to contact me.
Sincerely,
Mario