Idk why OP prefers them to be proprietary and permanently attached. I like the ac standard cables, as I don't have too many receptacles, and I don't wanna bother getting a power strip, ergo, anytime I switch between my Ampeg and GK I just plug n' play that one cable into either. I never had problems with bent contacts, and to be frank have had problems with permanently attached cords just frankly, ripping. Hell, not exactly amp related, but I constantly have to change headphones because the jack gets damaged so easily...I'd love to have myself some nice Audio-Technicas or Yamahas with a detachable audio cable...