A pipe organ was my first coral actually, and it's been a hardy trooper for me. I've had it 1-1/2 years now, and it survived the tank move (coral was in holding containers for a few weeks and got kind of neglected... lost a few things). They likes lots of flow... mine gets flow like for a leather or sps. They're suppose to like moderate to bright light, but I have mine on the bottom right now, and it's growing. Also have had it in the middle.
I've read the reason some people have success and others struggle really has to do with how it's fragged or cut of the mother colony. If't not cut off right, the polyps end up dying. I'm not sure how accurate that is, but makes sense to me (I can't remember exactly how it has to be cut). I recently had a frag of deepwater pipe organ, and it didn't make it... everything else in the tank (including sps) is fine.
I picked this frag in particular from the LFS because it looked very healthy. Most of the times I've been back, the pipe organ frags are a lot smaller and don't look very good. Kind of like my deepwater before it died.