I'd like to highly recommend working with hexcode.  He's friendly, professional, and also cares about the quality of the work.  When I was unsure about resolution sizes for sprites, he gave me a nice overview of different sizes and styles to help me make more informed decisions.  He's incredibly responsive to feedback and I'm very happy with his production speed as well.  Even though he's knowledgeable, he likes to learn and improve his skills too.  I recommend all to check out his work.  You will be quite happy.