Which would you choose (skimmer)

Hey guys, I have the choice of either picking the Aquamaxx Cones co-2 or the EM300.. Which would you choose?? Its for my 120DT that one day will be medium to heavily stocked with lps/sps and fish.. The quicker responses the better as I already ordered the Cones co-2 but wondering if I should step it up. The place where I'm ordering from doesn't have the Co-3 in stock so the EM300 is my only bet. Thanks