For me it depends on which deck I'm using. In my Pally control deck I prefer going second, since I don't have any 1 cost minions anyway but the possibility of a turn 1 Knife Juggler or turn 2 Harvest Golem is quite nice, or just saving the coin if I need a big spell like Avenging Wrath or Lay on Hands early.
When I'm using a deck that has 1 cost minions though(Warrior and Rogue mainly)I'm fine with going first IF I get the 1 cost minion in my opening hand. If not, I'd prefer going second.