I had a go on the Sonic FR 11m as well this weekend. First time ever on a foil kite (I had just come off the water testing the 13m Boost - nice kite too) and I must say I was suuuuuuuper impressed. It felt like it didn't really pull enough to get me going but somehow it had me up and riding with ease. Maybe this is just how foil kites feel, I dunno, but it was just very light and I was surprised to be riding because the kite didn't seem to pull that hard. Anyways, after 45 minutes of testing, there are two things that blow my mind on this kite:
1. Upwind ability. I was on a small TT and wasn't even trying to go upwind, the kite didnt seem like it was pulling that hard, but somehow I had gained 350m of ground in no time - 2 tacks or something. Just crazy!
2. Jumping. I have never flown so high and so long in such light winds (13 kts or something). All you need to do is steer it to 12 and pull in the bar (the faster/more aggressive, the higher you go). Similar height in jumps I have only achieved on my Bandit Six 12m in like 18-20 knots, so overpowered-ish and on the upper limit. Here on the 11m Sonic I didn't feel overpowered, on the contrary. The pull/lift of the Sonic is just straight up, it doesn't drag you downwind. Once off the water, this thing turns into a parachute or something, you just glide and keep gliding. A few times I got an additional little gust of wind that gave me an extra boost. Airtime is insane - at one point I was seriously thinking "holy shit am I ever going to go down again?!". Landings are smooth and supersoft. The Flysurfer sales rep on the beach said that he likes the 11m in like 20 knots, said it boosts insanely high - I definitely believe him, this thing is a rocket and will take you to the moon!
Compared to LEI kites I'm used to riding, the Sonic is slow to steer though, so forget about looping or using it in waves - it is not designed for this. This kite is meant to go fast, hard upwind, and boost high. I did loop it once or twice and then it pulls hard, and the loops take a long time to complete - I got punished and ate it bad when trying. Stability wise was very good - I screwed up a few times and rode right under it etc. but it never really fell out of the sky - it lost its shape once or twice but as soon as it got back in the wind window it immediately recovered itself.
So yeah, I've always been skeptical about foil kites but after trying out the Sonic I'm seriously considering getting the 15m for those light wind days to cruise around without a walk of shame in sub 10 knots, and boost high in 10+ knots. As soon as the wind picks up to 15+ knots, I can switch back to my 12m inflatable. Will have to test out the relaunch but should be fine as long as not dropped in waves, plus in light winds the water is normally calm anyways. Also, because of the slow steering you would really have to do something stupid to actually crash it in the first place. Perhaps not a good kite for beginners, but if you have some kiting experience with inflatables the Sonic could work as a first foil kite - it was my first time on a foil kite and I loved it!