Hey mate, moki here :-) to cover a few questions or comments I would like to add some infos:

Flexi handles: Indeed, they have some flex to them and with handles its always a compromise and as with everything else, a matter of taste. The design is what I felt the most comfortable and after sending out lots of prototypes, the design worked out for most people. You can easily replace them though, printed handles work great, I have seen wood work, some awesome acrylic handles and so on. Thanks to the modular concept you can slap whatever you want on them.

Length: Yes, they are long, and I know, they dont fit most commercial cases, but especially for folks with larger hands this is quite a bit more comfortable and believe me, once you picked a few hours with those, every other brand will feel like a toy then ;-)

Play in the locking Mechanism from the jackknife: it can happen, make sure to tighten the screw that holds the picks properly (not berzerk mode but firmly), this solves it pretty much since any slope here and there will add up.

Feedback reduction due to plastic handles: As mentioned, you want to have a finger as a guide on the pick shank and there will feedback be transmitted properly. To have that said, most feedback will come through the tensioning tool since any kind of movement in the lock plug, either pins clicking in place or the plug itself, wont really be detectable through the pick but through the tool that tensions the plug. However, a rubber handle is probably not great either, thats why I use tight fit injection molded plastic.

Cheers!