I have used this previously when it leaked. So I am giving it another try. After two uses, no problems. But it is not labor free. You must really be attentive to the cap, ensuring that it is tight and always clean it in warm water afterward. As a long time cyclist I have used this and other methods regarding GU type supplements. I am not sure that just bringing along a small plastic bag to use for the discarded individually wrapped product is more of a chore than using this product. I continue to test this proposition.

The flask is awesome , instead of carrying multiple individual packs of GU. I can fill up the flask and use as needed. No more mess of having the sticky empty packs in my pocket during runs or pack during hikes.

Easy , no mess, portable way to carry GU

I love this thing! It's cost effective, produces less waste, and really convenient. It's nice that if you only need a tiny bit, you can close it back up, whereas with the individual packets, if you don't finish the whole thing and want to save it it, it can get pretty sticky!