I have one and it appears to be a fairly hardy coral so far (I've had it since 2007).
When I acquired it from a $5 assorted coral frag tank I though it was a nickel-sized light-green mushroom coral at first when I selected it:
...except that it was evidently a stony coral when I handled it.
It developed into this: (these photos are a few years old it's a lot bigger now, with a lot of ridges but I do not have any recent photos of it as of yet):
Pectinia seems to fair well in moderate lighting. I've since moved it to a higher position in the tank and upgraded my lighting and it appears to doing well under greater lighting conditions as well.
It accepts food readily at night (mysis shrimp) when its tentacles are extended but does fine without feeding.
Speaking of its tentacles, pectinia can cast some fairly long sweeper tentacles nightly. In the last photo they extend clear past the right boundary of the photo: