Seaclones really aren't THAT bad, more like okay from a far but far from good. Even thogh seaclones aren't the best, they still work none the less and mine (rated for 200g -according to the LFS I bought it second hand from) has proven to be adequete for my 29 softy reef, however I'm not using the stock air valve, as I got mine used and it didn't have the air valve - if your having problems adjusting the air, then go out and spend the $2 on a different valve, from what I read the stock air valve is has got a few problems becuase marineland went cheap on the design. I'm ending up with a 1/2 cup of skimmate a week with my seaclone, BTW.
If your on a bidget and the seaclone doesn't seem addequete to you, I'd suggest that you build your own skimmer, as I would guess that almost all skimmers cost 2-10x more than it cost to actually make.