Psychobrew's turnkey systems are very nice, but their 3bbl system is a double-batch style which I'm not wild about. They do offer 100g kettles now, which is a step up, but I'm DIYing a basic 3bbl system myself right now and would rather have everything done to my spec in a way that I can continue to upgrade as I have the cash. Plus I know a lot of metal fabricators and have friends who can weld.
Depends on how much you want to spend, but for 3bbl from prominent manufacturers you're looking at "pilot" breweries. Premier stainless has a really nice system I'd buy in a heartbeat if I had the scratch, and Portland Kettleworks stuff looks fantastic, but I've never seen one in the wild- they're a fairly new company. Sort of somewhere in between Psychobrew and Premier Stainless by the looks of it. Stay away from brew-stuff.com, and I'm not a fan of Stout Tanks since their stuff isn't made here in the US.
I can't be arsed to keep up this list of what's in the fermenters, but hey, check out the cool brewery I own!
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