Well, Odie has only been on JWB for about a month so can't comment on his weight atm but he was on a worker food (he's a show though) - Dr John's Silver which he loved but he never seemed to gain any weight. He is deceiving as he's very fluffy when dry but looks like a skinned rabbit when wet
The good thing is he is eating a good amount of JWB whereas he wasn't on the other one.
How old is Candy? I'm giving roughly in the middle of the 10-20kg range which seems OK for Odie who is 2.