I've fished it for 2 36 hour sessions, including a day after the (in)famous pellet session. I have caught 1 smallish cat from Mill, and to be truthful have not seen many fish caught. But as someone else has said, it's very new.
I like the place and will be returning this year to try again. it's not the first place I've blanked and I'm certain it won't be the last.
A quick word on the cafe. The breakfast is brilliant value (at around a fiver), in my view. Everything is freshly cooked and best of all hot. I can (and do) cook at my bivvy, but nothing beats a sit down in nice surroundings and a hot breakfast.