I pay $15-20 for a 6.6lb bag of EVO. But it lasts about 3 months. The red meat is more than the chicken flavor, so that's why the price range. I rotate with Instinct, but I got my bag free, so I don't know what it costs for the 4.4lb bag.
I'm sure the bigger bags are less $$ per lb, but the 6lb lasts us 3 months, so we just go with that.