I don't like feeding all the grain that's in foods like Royal Canin, Science Diet, etc I mainly feed raw, but if I'm traveling and need to use kibble I get Nature's Variety or Wellness Core. Petsmart carries both now.
Just another sad story about how much Blue cares - Years ago I thought I would try Blue Buffalo Wilderness with my Sphynx cats. I had 3 cats - 3 days after switching them, one of my cats went down scary fast. I rushed him to the vet but they couldn't find what was wrong. His liver and kidney values where extremely high but none of the toxin tests or other bloodwork they ran gave any reason why. All my cats had just had full physicals including bloodwork about 3 months prior. He ended up spending 2 1/2 weeks at the vet near death on IV fluids and being tube fed before he was even strong enough that I could take him home to continue the treatment (I am a trained vet tech, and had an IV pump and everything else I needed - But he was far to critical to transport back and forth to the vet every day when I went to work since he needed to be monitored around the clock!) He wanted to eat but he was to weak. I took him to a specialist, they couldn't figure it out. Slowly my cat recovered after loosing over half his body weight - It was a very long, slow recovery. A week after the first cat got sick, my other male went down just as fast. I rushed him to the vet as well - but sadly he went into Cardiac Arrest within moments of getting there and as hard as they tried, he didn't survive. When I took my surviving cat to the internal medicine specialist he asked one question I thought was odd - "Do you or have you fed Blue Buffalo". I told him I'd just changed and he told me that explained a lot

. He said he'd had a number of patients with sudden serious and unexplained symptoms and the only thing they all had in common was being fed Blue

I called them and basically got the same response you did "the bags may vary from batch to batch" - OK, but my cats had never eaten Blue before, they where perfectly healthy, and suddenly I was thousands of dollars into vet bills on one and lost another. They told me I could exchange the bag - No thanks! I threw it away and went back to their original food (Felidae). My one girl that never got sick I took to the vet to be safe, and both her liver and kidney values where high. She's just had bloodwork done (they all had!) just 3 months prior - So we know it was a new thing, and almost certainly caused by the food. Not a coincidence that 3 healthy cats all had problems!