10K RPM drives are slaughtered by the Momentus XT (hybrid).
I doubt there is any significant speed up in regards to moving user documents to the hybrid drive.
When updating my missus's PC, I imaged across to the SSD,.
Later, I moved the user profile/storage documents to a standard HDD .. there was little difference in loading times, or delays for large email folders.
The momentus XT combines the advantages (speed & capacity)) from both SSD & standard HDD.
At $160au (in Oz), it's significantly (35%) cheaper than a current generation 64GB SSD ($270 - although you can get generic brands for a similar price - $150-170au) and a 500GB HDD - approx $50 (ex P&H).
If you want a super-speed PC with Giant storage capacity, go with SSD with a separate (cheap) standard HDD for storage.
Where this really shines is for Laptops, where an SSD is too small (or expensive) for permanent use ....
Or, when upgrading single HDD machines (like I'm doing).
If you've got older PC's or laptops used in your workplace, slipping one of these babies in and imaging the original HDD across to it saves $$$ in upgrading PC's
I've done most of my workplace with these, including the data array on our main server - standard HDD's still used for the boot drives. It speeds up network transfers from servers (reduces browsing delays & whatnot).
Honestly, these Momentus XT's are the best things since sliced bread