Doogie,
Obviously I wouldn't! I was just curious what the price difference was and glad I sold my Ref 5 before the SE upgrade came out! I doubt I will ever need another preamp with the 40th AE, it truly SMOKES the Ref 5 and I loved the Ref 5 when I got it!
I A-B'd them and gave the warm up advantage to the Ref 5 (1,200 hours on it and 4 hours playing time to warm up) v the 40th AE (550 hours and 30 minutes warm up) Their was no comparison, the 40th had EVERYTHING better! Micro and macro dynamics as well as a quieter background and better bass control. The shear speed of the 40th AE over the Ref 5 was unbelievable.