I got samples of it when NB sent me a bunch (they are really generous with their samples and fabulous customer service). Jackson really liked the taste of it! He loves kibbles that are a bit bigger like that (they are wide but flat, if that makes sense). There are a few controversial ingredients/fillers in the Alpha line, such as beet pulp and vegetable pomace that made me iffy to feed it. He did have SMELLY poo when he ate it.
If I was going to feed NB, I'd choose one of their grainfree limited ingredient foods over the Alpha. I do like NB as a company
and have considered feeding their foods but the only way I'd feed one of their LID diets is with canned food to up the meat content and higher the protein (NB is lacking in the meat department) in conjunction with feeding Jackson his pre-made raw. Some of the low proteins just seem really low for normal healthy dogs, but I just don't know.
We've had really good luck with Acana. He's mostly been eating that for over a year now switching between flavors but I'm currently looking for a second brand to rotate with.