Just asking for some interested folk who windsurf where I foil. Does anyone know if , when learning to windfoil , would it be easier to learn on Slalom or Freeride gear ? The guys who have asked me are thinking about getting into windfoiling with the intention of only foiling in light wind, 5 - 15 kts, on slalom foil gear on the lake. They're all slalom windsurfers.
I'm a Freeride windfoiler on the lake, and my guess is, and I could be wrong, that learning to windfoil on big slalom gear in light wind would be harder than on Freeride gear ? Just wondering what people think about this ? I'm guessing that light wind (5 -15 kts ) slalom windfoiling is harder than light wind Freeride windfoiling period and therefore harder to learn ?
I think early slalom foils pre 2018 where pretty bad, and when good freeride foils hit the market in 2019 lots of people progressed much better on freeride foils. However, the modern slalom foils are much better, so I think the argument that freeride foils are easier is less powerful now. I think it depends on what type of finning the individual is used too, and what type of foiling they want to do. As your mates already slalom fin and they are leaning towards lightwind foiling, it would be hard to go wrong starting out on slalom foils.
Seems to me that big slalom foil gear is more enjoyable and probably has more flight time than big freeride foil gear. some downsides to the slalom foil gear is uphauling those big cammed sail and as the slalom foils are more for straightline speed you can't easily carve.
If they are already on slalom gear they have good techniek, so learning to foil will go pretty fast i think.
I did the same and my first foil was a freeride foil. After 4days on the water (average 3 to 4 hours/ day) i could already fly 500m easely. I learned it in 8 to 10kn wind.
After 1year i switched to full carbon starboard race foil because i wonted more speed. Am also on a lake so wind is most of the time around 7 to 12kn.
So going to full racefoil i took 115 fuse, 1000wing and 800wing. 255 and 255-2 backwing.
With 1000 wing its also super stable but more fun because a lot faster then before.
You can start with a freeride foil but they will move really fast to some slalom /racefoi gear. 
I think body weight is also a factor. I'm smaller so learning on 800-1000cm race/freerace wings was not a big deal but I have seen bigger riders struggle with them. When they got on 1100-1500 wings, the equivalent area for their body size as the smaller wings for me, it all got much easier. The latest generation of mid-aspect wings, I think are good for this. The first generation of bigger wings, while they got up easily, both hit a speed wall pretty early and, gusty winds, made control difficult as a lot of energy was spent trying to kill excess lift.
For people who are on slalom gear all the time, I don't think dealing with a bigger, rigid sail matters that much as they are used to it already. Even at my smaller size, my previous light air gear was a cammed 9.5 so a cammed 7.5 as my "light air" foil sail was an improvement.
Lastly, it will depend on personality. Some people who ride slalom gear may not want to be slow. They won't mind the idea of going a bit slower than their fin friends but riding around on 12-14 kts on a big wing won't be that appealing if all their buddies are whizzing by at twice that speed.
I jumped from freeride foiling to race stuff after around 6-8 months? My windsurf skill wasn't that great before that either (arguably, it still isn't), but if it weren't for big sails and the race setup my time on the water on the foil would be a lot less. I've found it a lot easier at 200lbs to pump and fly on the big gear and 900cm2 front than on the freeride. The sea breezes here are often fairly light. I think it also was a function of setup and race gear (like IQFoil) is very consistent. My early foiling struggles were having no clue about the setup and needing a different sail/foil just about every time I went out due to different conditions during that part of the season. It would take an 8.0 and i99 for me to get going one day and another day I'd be overpowered on the i76 and a 6.6. I didn't have appropriate smaller sails at the time to ride the 99, and the 99 was getting me flying on most of the lighter days at non frightening speeds.
There are also a lot of youth sailors that I saw jump from freeride to youth race gear and they are already better than me in the time I've been doing it.
I think a bigger factor is being around other good foilers. If you have a race or freeride and someone is nearby with similar kit it makes it a lot easier to learn from them, and get advice or just see what to rig/do. And to learn things about dealing with gusts by significantly changing sailing angle or otherwise.
If they're already good windsurfers on slalom gear, they've got to pick it up way faster than someone like me, regardless of kit, whose baseline was really low. If there's a group of them maybe they could all get on similar kit so that their learning experiences could be shared and go even faster?
If they are into slalom finning, they should skip freeride foiling. It is not hard to learn with Race foils. They could even start with a course race fuse (115cm) and the first flights will be much more stable than with any freeride gear. They can use that long fuse for very light wind days later on.
