It's fun! I personally never have rigged bigger than a 5.3 on my sups. They are not meaned for planing to no need to go big. Just go out and enjoy some old school windsurfing, anything goes!
I usually use my SUP (JP Fusion 9.8) when it's too light for my other boards <15knts and only use a 4.0 or 4.5. Great stability for uphauling, learning, clew first sailing, back winded sailing and sail flips. The only downside I noticed was trying to teach my son he couldn't get enough forward momentum to overcome the downwind drift. I have purchased a Duotone Drift stopper but unfortunately haven't been able to convince him to have another go. Don't get too caught up on the sail, I was using my son's simmer kids rig 2.5 the other day in 5 knts of wind with no drama.
I haven't done it personally, but I know a guy that does. He's first out in the waves, even before the kites, they would just fall out of the sky, in the wind he can catch waves with. If all you need is to add a rig, there should be reasonable decent secondhand ones around.
It's great fun. I am currently using a hypernut 7'4" and largest sail is a 6.0 convert. It gets me out on marginal days when there are waves but just not enough wind. Planning on putting a mast track on a larger sup so I can get out when the wind is even lighter.
I think with your skill with surfing and supping i.e. you should have good balance, the big sup that you have would be a good way to learn to windsurf. Just try to start off with no waves and light wind. A sail bigger than 4m. Watch a few YouTube videos or even see if you can get a copy of "beginner to winner". When you can get the sail up and turn around okay then add small waves into the mix. It will take a bit of time so try not to get frustrated slowly slowly and enjoy your success.
That's awesome that you're thinking of trying out windsurfing! It's definitely a fun experience, especially if you enjoy surfing and SUP. As for getting a sail for your Fanatic Stylemaster SUP, I'd say go for it! It's a great way to add some variety to your water adventures.One thing to keep in mind is that windsurfing does have a bit of a learning curve, especially if you're new to it. But don't let that deter you!
Start with a smaller sail size to get the hang of things and gradually work your way up as you become more comfortable.Also, make sure to check the wind conditions before heading out. It's important to stay safe and choose the right conditions for your skill level. And hey, I found this article that might be helpful for you: Can a Windsurf Board be Used as a Paddleboard? It talks about using windsurf boards for paddleboarding, which could give you some extra insights into your gear options.
I bought a Fanatic StyleMaster a year ago exactly for this purpose :-) I had a Fly 10'6" but it was too big (for my 70kg) and the StyleMaster is perfect. Much better rocker and thinned down for waves.
I would highly recommend the HotSailsMaui (dacron) SuperFreak sails. They are perfectly suited to the task. Their ability to luff makes all the difference in the world. Find a used one 4.7 ~ 5.5 and you'll love it.
