I just made switch from Lei to foil kites, 2 years in on Hydrofoil, 75-78 kg on moses 590.
"I’ve found a useful guide is plus/minus 2 square meters on either side of its stated size. So a 10m foil would cover a similar windrange to an 8m lei (high end) and 12m for low end. This might help you work out which size to buy."
This is spot on for me too.
I have Hyperlink 9m UL, that I use 98% of the time. Our winds are often 10-18knots. It's perfect for freeride. Replaced my 12-9 Monos...way better for foiling... Bought a Hyperlink 7 that hasn't been used yet for 16-22 knots. And a used Sonic 2 13 for 6-10 knots. But I've been out on it in 15 knots, no problems, just not for freeride..
I raced against pro level guys first and only time on July 8. ( I suck at racing and don't have ambition) The hyperlink won't cut it. Another Swedish guy getting into racing had a new Soul 12m He put it up for sale after that race because he's serious about racing and realised the Sonic race and FS Vmg guys were screaming fast past him. That said, a guy on Breezes did well because his skills on Hydrofoil were good...
I don’t think you'll be happy racing on Hyperlink or Soul ( but these other guys know more than me). Freeride for 12-20. Get a Hyperlink 7 or Soul 8. free ride 10-18 a Hyperlink 7 or Soul 8/10. Freeride 22knots plus use an lei...
Racing, get a used race kite 11m then a bigger one like a 15m, then a smaller like an 8. Flysurfer Sonic 2, DIABLO, Sonic race, Ozone R1V2...That should cover you for racing. There's a lot of used race kites on the market. 2handkiteracing Facebook group.