It's just my personal opinion, but I think a Herbie style drain fits a smaller tank, just from the physical stand point.Would bean be harder to implement on a small tank? I'm thinking of having a 17x17x20 built and it seems like it would be excessive to do bean. Is it common for small tanks?
Less bulkheads, less piping.
I use a Herbie drain on my 66 gallon tank and a bean animal style drain on my 240.
Both are very quiet. Both are easy to use.