I've tried him with all sorts - including James Wellbeloved, Nature Diet, Barking Heads, Royal Canin, and shop brands. He's really not very food motivated, so we were having to tantalise his taste buds by adding things (cheese, eggs, etc) to his food just to get him to eat it (he would rather go hungry than eat something he doesn't like). I saw Ruff and Ready in the pet shop and thought I'd give it a try. It didn't look very promising (my partner calls it 'rabbit food' because of all the cereals in it)so we tried moistening it with a little hot water. It smelled quite strong and he wolfed it down. I've since tried it without the water and he's quite happy to eat that too.
Good to find I can get it on Amazon with free delivery with Amazon Prime as I don't have a car and it's heavy!