Simple answer is your SSD is just fine no matter which one it is because an SSD is way faster than an HDD. Read speeds and Write speeds will vary on specific disk transfer tests however for doing REAL WORK it turns out there isn't much difference between the end results from one SSD to another (but don't look at eMMC). Note the SSD in an SP4/SB is the Samsung SM951 and will server you well. Full Article Choosing the Right SSD for a Skylake-U System SysMark Benchmarks Choosing the Right SSD for a Skylake-U System PCMark 8 Storage Bench Choosing the Right SSD for a Skylake-U System REAL WORK - differences are negligible Bandwidth varies widely however you're limited by WIFI speeds, USB speeds, & real world applications; the use cases where max bandwidth is holding you back are few and very specific. If you happen to read where someone is going ballistic over Samsung this or that vs Toshiba the other it's mostly a Moo Point (like a cows opinion, it just doesn't matter) except for some specific use cases.