Charles C.wrote a review of Science in Sport GO Isotonic Gels on October 27, 2017
Familiarity: I've used it several times
The isotonic nature of the SIS gel means that you are almost drinking the gel. No worries about feeling like you have to chew your way through something that, ostensibly, is supposed to give you easy energy. Draw back being you sort of have to consume it in one take.
I like the gel with Caffeine and hit it about for the last quarter of big rides to give back both electrolytes and a little energy boost.