I also windsurfed for many years and really enjoyed it. However, surfing has always remained the activity that gives me the most enjoyment and connection with the elements and that's not going to change. Windsurfing provided an option to get on the water when it was too windy and/or not at a surf beach.
SUP surfing provides increased opportunities to get that buzz in waves from knee-high to well overhead and on mellow to heavy breaks. Downwind SUP is also excellent fun, but you do need big boards to get the most out of it.
Foiling takes surfing to (literally) a completely new dimension, and you start looking at waves you wouldn't have even considered before. I have just started winging, but the attraction of it is twofold:
- already having the foil gear, I only need the wing (packed into a small daypack) to open up whole new range of foiling opportunities
- it's how I'm going to more easily get into downwind foiling. Then the whole ocean/bay is your playground.
The main reason I lost interest in windsurfing is the amount of gear you have to lug down to the beach. No longer do I have to load 1 or 2 boards, 2 masts, 5 sails etc etc. just for one session. I just throw the foil, board and wing inside the car and I'm ok - even after only 7 sessions on the wingding - from 15 to 25 knots.
Sure, people are starting to carry around different sized wings, but they are easily packable and 2 appropriately sized wings will probably cover a range of 10 - 30 knots.
Unlike the windsurfers and windfoilers you don't need a fully loaded tradies' van to carry just your basic gear. I also agree with the comment above about how quiet and smooth it is on foil. I always know when a windsurfer is coming up behind me, from the slap-slap-slap racket they make through the water.
(Sorry if this is a bit long-winded, but I have some inner ear issues that are keeping me out of the water for a number of weeks and I have nothing better to do with my time atm.

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