Yes Unaware is good, but it doesn't even compare to Magic Guard. Magic Guard is so much better it isn't even close. Absorbing Toxic, being immune to entry hazards, leech seed, even ignoring your own Life Orb damage make it better by far. Also you don't have access to Soft-boiled with Unaware, so you would have to rely on Moonlight which only has 8 pp unless you wanted to use Wish + Protect.