My guess is pretty good. SSDs are far more robust than any mechanical drive, so it's only logical to use them as the main drive.
SSDs are particularly great for laptops. Standard laptop drives are 5400rpm, so they're sluggish. SSDs are substantially faster...my laptops boot much faster than with the mechanical drives I replaced. Not to mention, I can drop my laptops without crashing the SSD. I've had a much different experience with a mechanical drive.
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