Thats a question thats pretty much up to individual taste....
Becketts do an impressive job of pulling stuff from the water, but they require a powerful pump to feed them, and they are touchy to dial in just right.
NW skimmers are pretty much plug and play.....but they do need to have the air inlet cleaned out and rinsed w/ fresh R/O water almost weekly.
Downdraft skimmers are an earlier version of the Beckett skimmer. Less touchy to dial in but still require a powerful feed pump.
There are pro's and con's to each. I've never used either a downdraft or a Beckett, so I cant give a fair unbiased answer to this question. I didnt like how much electricity my last tank was drawing, and how much heat the pumps added to the tanks temperature, requiring a chiller, which drew more elctricity. So I went with a simplified system this time around. As part of that, I'm using an
H&S AF150-2001 recirculating skimmer.
Re-circ skimmers allow more contact time with the water, in theory allowing better removal of DOC's than regular NW skimmers. Mine is fed directly from the drains of the display which cuts down on the power used to run my tank and the heat added to it.
HTH,
Nick