Yes, I did it. I tried green juice. While the one I tried was probably as good as green juice gets - it's the one the woman at the green-juice place said is the most popular green juice, and has apple juice and ginger mitigating the kale - it's not for me. According to my husband, who'd tried a different green juice before, this was one of the better ones. It's possible we'd have both enjoyed it more (no way I was going to attempt the entire thing on my own; as it stands, half of a no doubt now-gone-off green juice remains in our fridge, as a souvenir of sorts) had we not gotten it immediately after tacos, which were, in turn, immediately after pastries. A juice cleanse this was not; perhaps if you're really hungry, it's more appetizing? Something about the aftertaste - celery? romaine? - set off my gag reflex.
That said, it was less weird than I was expecting. More... snake-oil-ish. I mean, it's some liquid in the general family of gazpacho or V8. It's not a new, exciting product, but vegetable juice or, with the addition of ginger, vegetable soup.
That said, sometimes it pays to be suggestible. Inspired by someone I follow on Instagram, I got a matcha latte, which was quite good. I went with soy milk, thinking that would somehow go together, and I think it did. Different from, but not necessarily worse than, regular (that is, milk-free) matcha. Vastly, vastly better than green juice, but with that same "health, health, health, darling" aesthetic appeal.