Bassists: what is the deal with Benavente basses?

I’ve never played a Benavente bass or even seen one in person - I’ve only seen pictures of them. As you may know, many of the Benavente basses, instead of having a horn on the left side, actually have the body itself extend along the fretboard, sometimes seemingly almost half the way up the neck.

Here is a good picture of what I’m talking about. I am unable to see how this would be a comfortable or intuitive shape to play on. It seems like a very awkward, bizarre, not to mention unneccessarily heavy design. I personally need to have the neck firmly gripped in my hand, and I cannot see being able to do this in a comfortable way on that Benavente.

Some of the Benavente custom models are really insane, such as this 11-string bass pictured here. I cannot see this being practical as an instrument. Look at that man’s hand physically in proportion to the fretboard - it is literally twice as wide as his hand.

Has anyone here played one of these instruments? How are they? Visually they look amazing, and I can’t imagine that they don’t sound awesome since they have such a large following among bassists, and part of me thinks that such an over-the-top design wouldn’t continue to be made if it wasn’t good. On the other hand, it just seems so impractical. So what do the other SDMB bassists have to say about these?