Check the sticky at the top of this section--it has some of the more YT recommended brands. Some of the companies will send you samples and coupons if you contact them.
You also may want to try researching your options on
various sites. The link below will direct you to several different sites examining a wide variety of options--commercial foods, home cooking, raw feeding, supplementing...
Dog Food Review Ratings
Do trial an error runs. Research what options you think are best for YOUR dog, try it out and examine the results. Do comparision feedings until you have found what YOU think is a good match for YOUR dog. Just keep in mind, what one person feeds theirs, may not be the best match for yours. You will be the best judge of what is best for him.