I have listened to the F206. I got to set them up myself and try them with different amps, spent a lot of time trying different setups. They're not my thing. I wish I understood, but every time I set them up I was surprised at my inability to really enjoy them. I also do not love the M105. The one I liked was the F35 with a subwoofer. Every time I set those up it made me happy. I wouldn't say any of these speakers sound bad, and I can hear things that I would objectively describe as better about the F206 than the F35. But, despite that I like the F35 better. Similarly, the M105 is no doubt a better speaker than the Sony SSCS5. But, I'd rather listen to the Sony. Our preferences are what they are. Interestingly, others at the shop agreed with me about the F35 being more enjoyable. It may just be the specific room/speaker interaction.
My take on the KEFs from trade show experiences is that their bookshelf speakers are great nearfield. I wasn't blown away by the big blades, although they sounded very good to me. There were two rooms with them at the last PAS, and one got very good bass response to happen. One thing I will say is that coaxial mid/tweeter has the same signature across the board. It comes across as slightly too bright to me, but not so much as to make me dislike it. I don't hear any specific magic from it. I love the coaxial concept, but to my ears a well matched midrange and tweeter in separate waveguide seem to do just as well.