These cups are convenient and keep well -- though they do not need to be refrigerated, we keep ours in the fridge. I'm not as focused on the taste as maybe others, since they're not food but rather a sacrament. That said, they taste fine. The only problem I have is that the seal on them makes them very difficult to open. I find people are often fiddling with them to try to pry the wrapper off all while trying to not spill the grape juice. It's such an issue that I've considered switching to another brand.
So far the fellowship cup has served its purpose. Great for camps, home groups but a little expensive for a large church setting. The only downfall is they aren't readily available in Australia and the postage costs a fortune.