I have one and it seems to work okay, but if have nothing to compare it to. When I did 5 gal batches I would just dump the whole boil kettle into the fermenter. Moving to 10 gal batches with a 20 gal boilermaker with hopblocker.
Just this weekend I did an APA with 8 oz of pellet hops and it keeps mostly everything in the kettle. At the very beginning when draining the kettle I get a few hops come through, I think these are the ones that fall into the hopblocker during the boil. After that it comes pretty clean. I drain pretty slow, gravity drain with valve about half open.
I can tell you don't forget to install the hopblocker before starting the boil. One time I was about halfway draining my mash tun and realized I forgot to install it. I first wort hopped on that beer (3oz) so I transferred as much as I could out of the kettle but did not have enough room for everything. Ended up installing the hopblocker with a sludge of hop liquid on the bottom of the kettle. After the boil I plugged up my therminator immediately and it took me probably an hour to drain into my fermenters. Not a good day
alpha
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