[Suzerain of Sheol]

Plate's heavy, but the way it's distributed over the body makes it fairly light in practice -- the main issue with fighting in it is overheating, which can happen very quickly. As long as it's well-made for the person wearing it, though, it allows full range of movement, up to cartwheels and backflips @_@ . (There are videos on youtube demonstrating exactly that...)

Chain on the other hand is about as heavy as plate, and all the weight rests on your shoulders and hips (assuming you belt it, which you'd be insane not). It's a lot more restrictive and tiring to fight in, but on the other hand, it's a lot stronger than movies make it look, too. Proper riveted steel chain with a padded gambeson under it can pretty much laugh off cutting weapons, and it provides solid protection against piercing, too, even arrows from anything but an English longbow. (Plate could shrug those off, but only if they were arc-fired. A direct shot could punch through, though it'd still waste a lot of momentum doing so.) Blunt force trauma is, of course, the main answer to chain, could even end up driving the links into the skin. That's what you had a shield for, though...


But yeah, chain's a lot better than Hollywood likes to portray -- they wouldn't have worn the stuff if it could hacked through with such contemptuous ease. There's an old Icelandic saga describing a duel between two champions, one of whom is rich and has chain armor, and it basically describes the match as "unfair" because the other guy literally can't hurt him with his sword.