I had the opamps changed in the Cayin 15 to wonderful effects. , the 15 which offers ss and tube outs. The bass is a tiny bit more pronouned through the ss, but the mids and highs are superior in the tube out. So thats how I listen.
My Cayin 17 offers only tube and am in the process of making my final tweak, changing the caps. I'll post a note on the results.
Makes sense to me that cahnging the cheap stock caps with mundork M series (not their best , not the cheapest) would affect the sound, as the caps is the very last stage that the sound passes before it exits the cdp.