I agree Rx8man,
I also have the DUDE and Nuforce Ref 9 V3 SE monos w/ TDSS level 3 upgrades. I am not searching for either component anymore unless something craps out. When I put NOS tubes from Andy's Vintage Tubes, the level of SQ that I now have is way beyond when I first got the DUDE and was the 3rd owner. I think the tubes in there were the original and I've had the DUDE for 5 years running way too often 24/7. Huge preamp, little amps, but great sound together. Throw in a little Krissy magic, and voila, aural delight.
Bob