Firstly, I have a natural affinity for Heroes rather than villains. I have only ever played one evil character (an evil mentalist).
I would be very reluctant to wear anything diabolical.
Lets face it, looking back at all the posts, none of us think this is going to end well.
I also have a hard time playing an evil/villainous character.
What if it was a "Good" demon? Are all demons bad? HellBoy comes to mind, Ghostrider, Nightcrawler?
Although you would have a hard time defending why you killed a "good" demon. LOL! Which would then imply that you are the evil being, slaying good beings and you would again be wearing armour that is dielectrically opposed to your own alignment, which again brings us back to....
"...none of us thinks this is going to end well."
Personally, I see this ending with you as a bloody sponge, squirting blood profusely from every little wound you take. "Poor guy. Grab a mop." The armour's defenses will kill you before any crit or bad guy does, but I am really interested in how it works out for you in actual combat. Please, keep us posted.
Remember: The only Good Demon is a Dead Demon