I'm getting to the end of a bag of Herbie Rings ;) (so about 2 months)
The dogs love them and they smell lovely but personally I think the dogs looked better and had better muscle tone/weight on
That'll Do! so next order I will be going back to that. I did have the pup on Herbie Rings mixed with Little Champ (mum was on this while pregnant and feeding pups) too and she was growing nicely, but turned into a very hyper lunatic

so for the last few days she's back on JWB puppy (turkey) and already she's calmer ;)
After winning a half sack of Burns 2 weeks ago (well the pup did lol), I've mixed the end of the Little Champ and the end of the Herbie Rings with an equal amount of Burns and will be feeding that 'till it's gone. Waste not want not and all that ;) I may have to add a little oil/fat tho to keep the fat ratio up ;) but I've made sure that the protein level matches That'll Do! so it shouldn't cause too much change in them ;)
After that it's back to That'll Do! for both adults and pup - They had better coats/weight/muscle/energy and it's cheaper too :-D now that's what I call a win-win situation :-D