IME Prizms can do a reasonable job, but they're no comparison to some of the higher-priced HOB skimmers. I get more skimmate from my 30g reef using a Remora than I do from my 65g overfed, stocked to capacity 65g using a Prizm. The Prizm is only there until I find a decent deal on a used Remora Pro (or finally break down and buy one on eBay), and then it's outta there to either be sold or live in a box as an emergency piece of equipment.
Yep, in a heartbeat, as soon as I find a good used Remora or Remora Pro. It's in perfect condition, and like I said it does a reasonable job but not as good as the 'better' skimmers out there. It'll be a few weeks before I can buy a new skimmer (just spent this paycheque's alotted fish money on powerheads, food and premium LR for the 5.5g) but if you want to PM me in a little while if you're still interested, maybe we can work something out.
ADD --> just so you can see what kind of performance I'm talking about, here's a pic I took a while ago of the colour and amount of skimmate I get from my Prizm in a day (24h).