It's... good? They do guided tours, so you get a bit more insight than you would on a normal visit. The on-site bottle list tends to be even sillier than usual, and there's loads of people around so it's a nice atmosphere and it's easy to find people to share stuff with. For my money it's not life-changingly better than a regular Cantillon visit, though. If I was planning a trip to Belgium around that time then I'd try to make it, but if it was only practical to visit on another day then I wouldn't lose sleep over it.
i have mixed feelings about it. two years ago, the december open brewday had a ridiculous in-house bottle list. but the crowds are insane. like...not sure how anyone can tolerate it. wall to wall people. i like cantillon more during the quiet times. i do not like it when it's full of people. it becomes noisy and really unlambic, if that makes sense. lambic's more about time and patience. crowds clucking away is the opposite of that. i'd rather visit cantillon in November during any of the brewdays and just take my time in there and miss out on some of the fun bottles for sale. a beer's a beer but an experience? it's more than a beer.
I was at brew day in November and had a great time. Manageable crowds and a nice bottle list. It was really one of the highlights of my visit to Brussels.
i was there on open brew day in '16 , i thought it was a great time, met cool people, had a chance to drink/taste every bottle on the in house list. I don't remember it being super crazy. Will do it again
