'Form ever follows function'! These are great, handy basses whose tone belies their compact size and weight. I have the 6-er and it's great.
The multi-scale helps even the tone and tension of the strings but I have to say, other than around the 5-8 frets, I find it disorientating, particularly in the upper registers when the multi-scale gets extreme.
This negative effect can be greatly reduced with good practise in not looking at the fretboard when playing. That said, I'm not entirely sure I'd have a bass with it again unless they did a less extreme multi-scale, say, like their 'Q' series guitars.