Like Mccrary,I would go with the Octopus skimmer.Obviously,your LFS is trying to sell you a skimmer they sell but Octopus are better than ASM skimmers and cheaper to boot.
Those Octopus skimmers are hot,hot,hot!I'm not sure what online vendor has them in stock at the moment.Premium Aquatics do sell them,I use them all the time-a good reputable online vendor.