Yeah I just want to disenchant it to have it. Nightingale and Dark Brotherhood armor is too cool to destroy. ;o;
You can't Disenchant those, anyway so you're protected from yourself.

I think it's more a quality of construction that gives them their buffs instead of an Enchantment. Plus, you could always replicate them before you disenchant them - like I did with Linwe's stuff.

Edit:
for personal experience, muffle, and waterbreathing to a much less extent, become incredibly rare at higher levels. i've had more luck at level 10-20 than 50+.
I had a hell of a time finding both of those after 50.
