Smidge. It's permethrin-based but somehow seems to work better than other potions with that ingredient. Ii haven't tried it for mosquitos.
Smidge is very similar in consistency to SSS so I suspect its a combination of permethrin repellent and and SSS midge-beak-blocking-slime.
SSS stops the bites but it doesn't repel so you're still in a cloud of the feckers even if they can't bite you. Its not much cop against anything else that would bite you like mozzies, ticks, cleggs, ferrets, sharks or tigers. They'll still bite you but they'll regret the lingering oily aftertaste.
If you're abroad then.... whatever people are selling locally is what most likely works. We had a locally bought bottle of citronella oil break in our luggage when we were cycle touring. We reeked, kept dropping things, cos everything was oily, and nobody would sit next to us in restaurants. Stopped us getting bitten though