For running, the value in these shoes is that it forces you to “run correctly”.

Similarly, my badminton footwork was never consistent. At the end of a session I'd be clunking around. In these however I'm much more nible, lighter on my feet (with no loss of speed).

As a league player I doubt you have this problem.

I will say this: find out local retailers from Vibram's website, and if it's on the way, try them on. The first thing you notice is how hard it is to get your toes in the slots (though it becomes really quick in a week or two).

Then there's how light they are, how you can move your toes. You stand up, and have to relearn how to balance – most shoes have raised heels, so you put your weight through there,  instead of around the middle of your foot. My balance is now much better.

Your foot is much closer to the ground so you feel – well, more grounded. As for the stability issue – have you ever rolled your ankle while barefoot, or does that happen when your shoes have thick soles you trip over?

Ankle support – I don't think normal badminton shoes have this anyway, do they?

Cushioning – a very good point. A problem that would only arise during jump-smashing. This model has an insole that does provide some cushioning, but nowhere near as much. That said, a good landing in any shoe would have you landing on the balls of your feet, sinking down to absorb the impact with your calves and arch (which is supposed to be weakened by lack of use due to conventional shoes). So this may not be that much of an issue (unless you are very heavy).

Finally, of course, there is lifespan to think about. If it does last you 18 months will that be much longer than your normal badminton shoes? These could even be cost efficient in that sense. If your surface is too abrasive (e.g. concrete) it'd rub through the soles very quickly, but wood should be fine.

If your club allows, try standing on a court barefoot (no socks!). Then try a few footwork patterns. Knock a shuttle about (nothing too fast, truly barefoot that will bruise badly). if you like what you feel, or are just interested, try on a pair in a shop. Sizes are very specific, so I'd only get it done in person.

TL;DR

Try standing on a court barefoot, hit a few shuttles. Compare it with wearing shoes. Then try some on at a store. Make up mind.

Don't worry about ankle support, look at how badly it affects your jump-smashes.

Final Note: you may be so used to badminton shoes that these would just be too dificult for you to switch to. Discounting them without trying them on first is a mistake though.

All I've said above are my own findings. I have absolutely no comercial interests (here or elsewhere, I'm still in school).

Marc1313 – that's pretty cool! Which ones do you have?