I've tried the java juice and didn't really like it. But it was only one time, so I can't say for sure.
As for the issue of cleaning the french press: I really don't mind that part of it. I use a french press at home for my coffee, so maybe I'm just used to it. But when I'm at a base camp for a couple days or more, I bring a big dromedary water bag that holds 10 liters. Fill it up the night before so I don't have to pump in the morning, and I'm never short on water to clean up if I need to. Or I just leave it until after the climb, and hang the thing so no rodents get into it. Either way works for me.
But, admittedly, the coffee doesn't stay hot a long time, as it is a "drinkable temp" right out of the press....that's the downside, but I don't take it with me anyway. I guzzle and get going.