Speaking as a former defensive tactics instructor and someone who used to sell police equipment including all manner of less-lethal tools, I don't typically recommend gel of foam. It's only advantage is the lower risk of cross contamination. The effectiveness of pepper spray increases significantly when it can be readily inhaled and affect the respiratory system. Fog and cone patterns are much better at this. Even a heavy stream pattern will splatter a bit. If you're using gel and I am wearing glasses or just throw a hand up, very little is likely to get past into my eyes or be inhaled.

If you or anyone has questions about pepper spray or other self-defense tools, feel free to ask