There are 2 versions of the soft paddles out there...and if you're not careful you can buy the version 1 that doesn't have any form of locking between the layers. And as people find out when the 2 layers get out of sync you'll end up with cyclone problems.
I had a version 1, but I managed to lock the 2 layers together with small nails coming up from the bottom layer. All worked great until the paddles lost their lock on the middle spindle and got out of sync with the power tube...ie chopping balls.
Some of the cheaper paddles are completely pointless, having no stability at all, so be on your guard. Many vendors (ebay especially) are selling lots of crap.
Its best that you buy the paddles from somewhere where you can physically touch them and feel just how rigid they are. I bought a great set that have not given me any issues from BEL.
D.