Crucial RAM is not necessarily the same as the Micron OEM modules. Crucial sells some modules manufactured with other brands of chips, and even subcontracted to other manufacturers entirely. They beat the "Apple uses us" drum constantly, but in fact Apple has never, and will never, install Crucial brand RAM.
As far as performance goes, your Mac will run all RAM (as long as it is compatible) at the same exact speed. I have seen no evidence that Apple motherboards can take advantage of lower latencies in DDR RAM, and they certainly do not clock themselves higher.
There is nothing special about "Apple" RAM (other than you get a one year warranty instead of lifetime). Apple buys RAM in bulk from OEM suppliers such as Samsung, Hynix, IBM and Micron. You can buy the same modules from third party sellers. Just be sure that your seller guarantees the RAM for use in your model, because there are issues in chip configuration and SPD settings that can make a perfectly good module incompatible with a Mac.