I have a question ...when limiting the bandwidth for an account in WHM (Limit Bandwidth Usage), will it actually limit the bandwidth for that account? Or will it allow more than that? Since Bandmin always shows a higher bandwidth usage.

The bandwidth limitor will look at the byteslog stats which I believe will only show http bandwidth usage. bandmin calculates total bandwith - such as ftp, email etc. So the bandwidth limitor will limit the users only to their http traffic, which usually will account for 90% or more of the total bandwidth usage.

Unless you have a client that is an embedded software developer who receives and send email attachments that are mb in size :(