To clarify, the brewers are made by different people, but CT Guy of KIS sells both, his and the one that Microbeman sells (Microbulator 50). I have not seen it in person, but the videos are pretty sweet, and once I outgrow my brewer, it seems the next logical step.
As far as how loud it is, I'm sure Mm will chime in at some point, but I imagine it is fairly loud. He states that he uses the Eco Plus Commercial 5 (4 CFM Max). I have the Eco Plus Commercial 3 for my 5 gallon brewer ( a bit overkill) which is really loud, and I am currently trying to build a muffle box for it. Even with it being on another floor with the door closed, I can still hear it when I am drifting to sleep.
I sort of got used to it, I just pictures waves crashing and microbes fornicating, having some good clean aerobic fun!
"The door to novelty is always slightly ajar: many pass it by with barely a glance, some peek inside but choose not to enter, others dash in and dash out again; while a few, drawn by curiosity, boredom, rebellion, or circumstance, venture in so deep or wander in there so long that the can never find their way back out."