Graham Phantom to Supreme

I would like to know if there are any Graham Phantom II owners who have had their arm upgraded to Supreme status. If you can provide approx. cost and turnaround time that would be much appreciated along with comments on the sonic improvements post upgrade. I am using an A90 as my primary cartridge and a Dynavector XV-1's mounted on a second armwand as a "spare".
Thank You
I upgraded mine and was pleased. The cost was $800 at the time, though I think it's gone up since. Turnaround time is up in the air. Mine took a few months but I've heard of much longer waits. The most obvious improvement was in depth and quality of bass but everything became a little better, more resolving, more organic.