Hello...I think it's great you want to switch to a better canned food. Some of the canned food Snickers was successful on was: Merrick, Wellness, and now we use EVO. Evo is higher in fat, but we use so little every morning, that I have to freeze most of the can in portions or else it will go bad. Snickers is only 3.3lbs so if he gains a few ounces on the EVO canned, I don't mind, but I am watching closely. We also use EVO kibble which my pup adores. Royal Canine is not the best kibble either (some controversial ingredients), but if your dog does well on it, GREAT!! You can see how most foods ranked up on:
Dog Food Analysis - Reviews of kibble Best if luck to you....