Very interesting thread / question!
I have a SK8 750 since a couple of months with the "default" C160 XXXS monoblock tail.
I bought it with the sole focus to ride waves (small but steep wind waves, no ground swell, Baltic Sea) and to check whether those super high-tech high-AR wing foils make sense for kite foiling.
I´m riding it with 3/4/5 m² Ufo (sold all my Peaks after testing the Ufo), not in really light winds I have to admit. It gets tricky with the 7 m² Ufo in light winds, because of the speed and glide of the SK8. You very easily outrun the kite. But no prob at all in strong winds with the Ufos. You simply can forget the kite no matter how much you´re racing downwind / down the line. PURE JOY!!!
The SK8 is phantastic! Coming from a low-AR 950 cm² Alpine Freeride/Wave foil, the SK8 is so super efficient. It needs hardly any kite pull to get and keep going, and it is really fast. Even the smallest bumps (knee high) are becoming pure surfing joy. You can use silly-small kites with the SK8, I also bought the 3 m² Ufo now because I was overpowered from 20 kts with the 4 m² Ufo on the SK8.
The SK8 turn almost as tight as the Alpine foil (which turns super tight) and is much better in all other aspects. With the only exception of weight. The SK8 is much heavier than the Alpine setup (3.2 kg with 95 cm carbon mast vs. 2.6 kg for the Alpine with 80 cm mast). But also much more robust in construction, and super easy to assemble / disassemble.
However, I would buy the 650 instead of the 750 if I could make my decision again. The 750 is already slightly too large for my taste, particularly if you plan to ride very fast most of the time. Stall speed of the 750 is very low, around 15-17 km/h (with 75 kg). Absolutely zero increase in front foot pressure with increasing speed. I guess the 650 will turn even tighter with hardly any loss of low-end stall speed.
And I would NOT recommend to buy it with the XXXS tail because it is too pitch sensitive. It took me some hours to adjust from the (very stable) Alpine, and I´m still not able to do powerfull cutbacks due to that pitch instability.
I will hence buy the new C160 XS tail (longer than the XXXS) when it will be available, and I will chop it down to 120-140 cm². That will increase pitch stability without compromising on the turnabilty or reduce glide.
Read the comments under the youtube videos of MrBennetts! He is giving superb advice on the f-one and AFS foils, how to optimize their riding characteristics. And he answers every question. Super nice guy, and without a doubt the best prone / wing wave foiler on the globe.
MrBennetts was riding all sorts of foils, but it seems he prefers the f-one SK8 650 (with a rather long "short" fuselage and an extremely chopped-down C200 stab (120 cm²) over most other models / brands. Recently he also seems to love the AFS Silk foils a lot. Read his comments, really insightful!
You can use the SK8 either with the "monoblock" tails or with the "conventional" carbon fuselages / separate stabs. This opens up a lot of space for adjustments. (if your pockets are deep enough...)