I've experience with a Seagate Laptop SSHD (the post-momentus one). my Son's MBP C2D. Previously had a WD Blue 500GB in it. The link cable to the motherboard had gone, though I didn't understand that until I'd bought the new drive.
Anyway, installed the new cable and drive, and restored the machine from the WD500 drive using disk utility. Super.
Impressions? For general use, web browsing etc this C2D (2.5GHz?) with 8GB RAM is nearly as snappy now, with the hybrid drive, as my 2011 MBP i5 2.4GHz with 16GB and a factory seagate 500GB conventional HDD. I'm very impressed. It uses less power (longer batty life), is slimmer and runs cooler. And it was inexpensive!