MacBook Pro Compatible SSD Drive Upgrade Recommendations
Although many older Apple laptop models may now be limited as to which version of Mac OSX they're capable of running, when properly formatted for MacOS there's no denying a MacBook Pro SSD upgrade can breathe unprecedented new life and performance into any aging Mac. Thanks to backward compatibility, even older SATA I and SATA II MacBooks will perform as best they can with a fully compatible 2.5" solid-state SATA III drive that's the norm of what's currently shipping.
Things get more challenging with newer MacBooks starting in 2012 and beyond as Apple started transitioning away from 2.5" hard drives to custom pin-out SSD drive MODULES. Look to OWC - Other World Computing and Transcend for 3rd-party aftermarket Apple compatible SSD module upgrades - though note they're very MODEL-SPECIFIC depending on the year it was released and whether it's a Pro or Air MacBook - shop carefully! Use Apple System Profiler to identify your exact MacBook model name and numbers.
More recently, as in 2014 and later, Apple began the shift away from the Serial ATA - SATA interface towards the much more robust and higher-bandwidth PCIe connectivity. PCIe is poised to be the dominant solid-state drive interface for the next 5 years and beyond. But once again, custom pin-outs from Apple will severely limit your aftermarket SSD drive upgrade choices.