I've got the older 1st Gen 500 GB Momentus XT humming away quite nicely in my 2006 Core Duo MacBook. The paltry 8 GB of Flash is a significant weakpoint of the Momentus XT, and that Flash memory is used by the drive as a read cache; all writes go directly to the hard drive. On the upside it is a 7200 rpm drive, with a healthy 32 MB cache.
In terms of price/performance, it normally doesn't beat out the combo of a decent large hard drive and an SSD, but it is worth looking into if it's on sale; I got mine when one of my local dealers had a $50 off sale; leaving it costing about as much as an equivalent 8 MB 5400 rpm drive.