Currently 15-5 with this after a casual day playing in masters. Weakest card is Yetipult but it's a necessity against aggro and routinely sniping Runehammers. Cobalt Waystone has over-performed as the best card of the new set for this deck.
Best advice is aggressively mulligan for storms and always mulligan for 3+power hands. You really want to make power drops each turn.