I see if a vibe can be easily heard through a door, and if so, I give the vibe 3 bees. We have French doors to our bedroom (with glass panes) so I am pretty sure sound travels through there a little easier than through solid wood doors. I'll usually test during a period when there's some white noise going on instead of when it's dead quiet. 2 bees = can't be heard through a door, or you have to strain to hear it (i.e. listen for it). 3 bees = can be heard through a door without even trying (like if you walked by the door, you'd be like "What's buzzing in there?").

I don't think it makes that much difference, though. If I see 2 or 3 bees, I know it's quieter than a 4 or 5 bee toy, and that lets me know there will be some degree of discreetness. We can't all use the same toys X feet from the same design/material door in the same type of room (carpet absorbs sound, tile makes it echo more, etc.) so rating differences are expected. If a product has more than one review, I like to see how different people rate the noise (and power) level. I personally wouldn't be turned away from a toy that I otherwise really wanted if it had 3 bees as a rating instead of 2.

Interesting thought. I would probably go with 2 bees if it's a hard choice or whatever is closer. As is, the hint for 2 bees doesn't apply to me at all because I cannot hear my phone vibrate or feel it actually. It lacks both the vrooms and bees. LOL But the way I view bees is that 2 would probably be something someone could hear in the same room, through only a thin sheet and 3 is something significantly louder. There's really no comparison between the two for me at all.