My dog was on Fromm LBP for like three years because he wasn't interested in other food. We sometimes had problems with him eating the LBP as well. We did get another dog, so a bit of competition did get him to realize that he needed to eat his food or otherwise he would be SOL. He is also a bit hypoglycemic, and will vomit bile if he doesn't eat on a regular basis. To the point where its kind of cruel to play the "take the food away after 5 minutes game" because he just doesn't really care about eating sometimes. Like...he'd vomit bile, even when there is food in his bowl that he could've gotten to all day.
Recently, we went to the fromm grain free formula due to higher protein content for higher activity level. We just started their new Lamb and Lentil formula...and he's eating like he's never eaten before. He'll actually wait for you by the food container when you go by it and start scooping food into the bowl and dives right in when you put it down. It's like $52 a 26lbs bag by me and with two full grown dogs getting about 3 cups each a day it last a little more than 2 weeks.