'Hohner sells an "Extreme Bending" Harmonica with standard Richter tuning, but with auxiliary reeds that are supposed to make it possible to play chromatically. I'd quite like to try one next time I have 99 Euros lying around. Has anyone here tried one? I wonder whether it's possible to play the "accidentals" without too much "bendiness".'

Depends on two factors: your skill level, and your tolerance for "bendiness". If you are a "mid-level" player, and you have to play some fairly quick bends, they will sound "bendy" - but they will be going by quickly. The more accomplished a player you are, the less "bendy" the bent notes will sound (assuming you want them straight), but they're unlikely ever to sound as straight as they would on a chromatic.