Merrick BG gave Snick the runs
I tried it way back when he was transitioning off Merrick's Puppy Plate to adult food. We ended up going with Evo at that time and used Evo for about a good 6-7 months with NV raw. Then Snick decided he was sick of Evo & NV and now we use Acana supplemented with Primal raw and he is loving to eat again.
I'm very happy with the foods I am currently feeding. Champion Foods (makers of Acana and Orijen) won pet food of the year this year. I am knocking on wood neither Acana or Primal come up with "sudden" accusations of questioning of ingredients or quality control. I'm nervous now with the recent NV issue of charcoal, and have heard "bad" things it seems about all kibbles that are out there. Even Acana apparently has changed their ingredients and some feel is for a negative effect.
Acana's grainfree formulas come in 3 types which is fantastic. I use the chicken based (Prairie Harvest) when I feed Snick poultry raw and the lamb based (Grasslands) when I feed red meat raw. Keeps things interesting for him I feel.
I've been all over this section lately due to concern, and have seen that you are trying a large array of foods. I really hope you find one soon that all your pups can stay on without fuss. It does take forever. After all the reading and investigating...it seems the only 2 kibble companies I would go with are Champion Foods and Natura Foods. Of course this is just MY opinion
Good Luck-
Snick & Viv