The advantage of tef-gel is that it's a bit sticky so it tends to stay in place better than alternatives. You can find it on ebay for not much more. Be careful shopping because it comes in different sizes which are all for some reason about the same price. Get the syringe type as it makes it easy to apply to the screws/bolts (and handy to store in your tool box). A small tube will last you for quite some time.
If you get some on your fingers then get fingerprints on your foil wing, clean it - this goes for any of the things you are considering, btw. It seems to induce ventilation more than one would assume. It's not, however, harmful to the wing itself.
www.ebay.com/sch/i.html?_from=R40&_nkw=tef+gel&_sacat=0&_sop=15If you use grease, you can get a tube of marine grease at an auto shop where you can get your grease for your bikes (if you aren't already), just avoid the heavy high temp wheel bearing grease. For those new to the topic, a little googling will find you a wealth of info on various bike forums.
www.autozone.com/greases-and-gear-oil/marine-grease