Kate isn't a Newf, but I'm adding my bit anyhow!
When we brought Kate home from her breeder, she was on Eukanuba Large Breed Puppy. She did ok on it. At one point, she started getting really picky with it (not eating much). We noticed one week that she had grown really fast within that week. It freaked us out a little...
We made the switch to Canidea All Life's Stages Formula, and I would seriously be their spokesperson, I absolutely love it. Not that Kate's poops weren't firm on the Eukanuba (they were), but on the Canidea they are firmer, smaller (and most importantly) she poops half as many times! I know it's poo (but) it doesn't stink as much on Canidea. She eats a lot less. Her coat is so shiny. She just seems to be "functioning" better on it. Another important aspect (I think) is that it is highly pallatable - Kate goes nuts for her food (for the most part). She wasn't really interested in the Eukanuba...
Here's a comparison for you. I live in Canada by the way, so this is in CDN $'s. A 40 lb bag of the Eukanuba costs $67 and lasted Kate approx 3 weeks. A 40 lb bag of Canidea costs $51 and lasts Kate approx 4 weeks. It is a hollistic food, and costs less! Part of that reasoning is because of the advertising (Eukanuba/Iams advertise like crazy, Canidea doesn't)...
Honestly, I just love it and am so glad it was recommended to me by fellow BPOer's! I'm not against Eukanuba at all, I just see the differnce in our Kate since making the switch to Canidea and (well) - that's all I need! I would suggest reading the first 10 ingredients or so on foods you are choosing between. That really tells a lot about what you're feeding your dog...
Good luck!