Crucial = Micron which is an OEM supplier to Apple. For years now I've used their generic RAM in my Macs w/ no issues. They also have Mac specific RAM, but it's always a few $ more and it's the same as the generic down to the CAS rating.
Kingston. They used to be the best back in the 90's. Their specific RAM for Macs is great, but way overpriced. I use to use their ValueRAM but every now and then I'd get bad sticks, or at least sticks that were not up to Apple's standards so I stopped using them.
Corsair. Never used them. Supposedly they are good, but Crucial works so why take a risk.