I did fight blood angels mech spam to a complete draw.
I beat an ork player with combination battlewagons/kanwall/horde, even after the mission screwed me over 1st turn. (It was basically like Imhotep's lightning thing, first turn killed 4/7 of my guardian jetbikes, they ran off the board, and then wrecked a vyper squadron)
Though I will agree with your deathwing assesment. Everytime I've played my deathwing vs my friends footdar, it's not even really a challenge. So many missiles, and the one volley of melta fire from my ravenwing make short work of wraithlords and avatars. Once in combat, my terminators love me some guardians, and if he brings seer council, then I put 3 squads of terminators into combat. Really the only thing that worries me when I face footdar are harlequins, and I usually send in my command squad with belial in front, to soak up the amount of wounds they can put out.
Though I will admit, I mostly play footdar for the challenge or when I'm facing a newer or less experienced player.