From what I researched, there are two types of M2, the sata version and the pci-e version. both look alike in the form factor and my intentions is to put in the m2 into a 2.5" hard drive enclosure and put in my 2012 mbp. I think the top of the line SSD would be the Samsung 850 Pro, but with news of the 890 pro coming out I was considering getting an M2 and a 2.5 enclosure to make it work in my mbp. my question is if anyone has used an m2 to 2.5 inch enclosure for their mbp. speeds of the new 890 pro are supposed to be above 1000mb r/w and I'm hoping that the speeds will convert over with the 2.5 enclosure and not experience a bottle neck. any advice or suggestions is appreciated. I just don't want to buy an m2 ssd only to find out it wont work in my mbp and I end up have to make it an external. thanks for your guys knowledge. I've done research, but I need some clarification on the m2 ssd itself and the enclosure.