just to add my 2 cents worth..
i am using a beckett 648 right now..
with an extremely high bioload considering my tank size....and i feed tons of food to my fishes everyday..twice or even thrice daily when i am free..
food includes..tons of Ml's receipe..cyclo and pellets..
my water turn milky and takes abt 15 minutes to clear up..
my tank has no DSB and is only 7 weeks old..
but my beckett has performed very well..keeping my no3 at 5ppm..
it was even at a low of 2.5ppm last week but i intensified the feeding this week in order to tempt my AT further to feed..with some success already..
i cant comment on the other skimmers like euroreef and BB...but i seriously think that a beckett is good enuff...with a high bioload and so much feeding..its at 5ppm...and i have never changed my water since day 1...all relying on the beckett to do the work...no DSB, no Refugium...