It is normal for the first pint in a keg to have some yeast, regardless of what yeast you use. I have a . I don't use it all that often, mainly for berry ciders. Easy enough to make one yourself. The main trick I've found in using it is to invert the filter at the end. This forces almost all of the brew out of the filter into the second cornie.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
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