Question about Crucial Mx300

The Crucial MX300 was a bad buy, because the performance is terrible.
For updating Apple products, I recommend using only Samsung products - currently the EVO 850 - because OSX can handle them best.

I installed it in an early 2008 MacBook 4.1 and it works as well as can be expected in a 9 year old computer. I can't judge the performance compared to other SSDs because the interface is an older one and therefore no SSD can be very fast. I used to have a 256GB EVO Samsung in the same old MacBook. I don't notice any differences except that I have a lot more space now. I can't judge how it works in a new MacBook.