How do they compare? I'm unsure of which one I should use.

Compare them yourself here . . .

http://www.uesp.net/wiki/Skyrim:Armour

Ancient Shrouded Armor for the win!!!

Ok, I just noticed that Nightingale Armor isn't on that page. You can find info about it here . . .

http://www.uesp.net/wiki/Skyrim:Leveled_Items

I would tend to agree. Ancient Shrouded Armor has better armor value and enchants overall than Nightingale, and is available at the lowest level you can complete the DB chain at whereas Nightingale is levelled and doesn't top out till level 32.

Dragonscale is good if you can smith it, but even then you should still wear the ancient shrouded gloves, since I don't think you can replicate their enchant, which is godly for stealth melee. If you're a light armor non-stealther just stick with dragonscale.

Well I killed the dark brotherhood, but on my second playthrough I will get the ancient shrouded armor. But from the stats I think I may just carry both for now and see how they compare in combat among other things.

Thanks for the help.

enchanted smithed dragonscale will generally always be better - for example, you can have muffle on boots plus another enchantment, such as 1-H, pickpocket, sneak or resistance. but of course it depends on your playstyle. I use my bows more, so I dont use the gloves (ancient shrouded or nightingale) except in specific situations.