I am very happy with the 500GB Momentus XT. I've used X25-Ms and the OCZ Onyx in laptops too. It's not as fast for sure, but with common laptop usage (loading a handful of the same programs), it's well-suited, especially since you can get 500GB for just over $100.
After replacing an 80GB Intel SSD with a 500GB Momentus XT, the first thing my sister noticed was not the speed, but the fact that she could hear the drive again