I have an Macbook Pro 13 Retina, Early 2015. I ended up buying this drive: http://www.transintl.com/review/product/... (1TB) SSD to upgrade my 128GB Drive I bought with the system. Overall, it took from the 19th -> 28th of November (delays most likely due to American Thanksgiving). I installed it today and the bench marks are in the 1300 range for read/write, so it appears to be using all 4 channels to communicate. I believe the OWA version uses only 2 channels (could be wrong, but you should verify).