I have only used it once so far but here are my thoughts...
1. The instructions of how to use this with the vest were not provided and the online photos didn't really improve things. I could find no "clip" to secure the tubing to the vest. I tucked it in but it kept coming out and flopping around. The lid was also in the way. I see the vest 2.0 has loops for the tubing which will definitely help but that's further expense (I already have two original vests!).
2. It's difficult to fit the bladder through the opening of the mesh pocket. I managed it but it's tricky. Again vest 2.0 appears to address this.
3. You have to suck quite hard to get any liquid out - not ideal when you're running.
4. There's an awful taste from it. Hoping this will fade over time.
5. The tubing is too long. I plan to cut it but again instructions regarding this would be a good idea.
6. A second lid for the bladder would be handy to use it separately to the tubing / and or to ensure no leaks in transit to races etc.

All in all it's OK but if you have an original vest like me it might be worth adding some loops to secure it properly.

Very disappointed with this, the bladder does not fit the vest properly and it is difficult to get the vest on when the bladder is in the vest as it keeps falling out. There is no securing points for the drinking hose and it dangles quite a bit. I would not recommend this what so ever, while I love the vest itself it seems the bladder was a cheap after thought.

Not happy with the bottle of I’m honest.. It doesn't fit in the vest properly, to the point where it would fall out while running.. Would return it only for the fact that I have used it..! Would not recommend this product whatsoever!!

I have bought the pink new edition cat and would like to see a demonstration video telling me how to thread it .I have never used a water bladder

There’s a horrible taste of plastic off this bladder. Have washed it a few times and can’t get it off. The vest is great, pity about this product