I will expand on what I previously said. I used a Fairtex pole bag for roughly a year.
Pro:
-It's not going anywhere. If you want to throw 20 double kicks in a row, you can. You could always use ties on a normal bag for the same effect.
Con:
-It's got a pole inside. All bags get lumpy and need to have filling adjustments from time to time. They all develop "hard spots" without careful use. In the case of this bag, it can be incredibly dangerous to strike areas that lack sufficient fabric stuffing.
-It's not going anywhere. It's pretty hard to circle or work angles on a bag that is probably only being used for the corner of a frame for heavy bags. This is not an issue if you're using this bag on a pole that is not attached to anything and you can freely move about.
-It's freaking huge. You're not clinching it.
-It comes unfilled. $250 and you still have to spend an afternoon stuffing it. You could always hire some midgets to get inside and have it perfectly stuffed.
-It's freaking huge. Your foot is hitting the ass end every time. Even more so than hitting other large bags, like a 4' 130-50lb'er.
Definitely wouldn't be my first choice. The only reason I'd buy one is if I couldn't fix a hanging bag, but it would oddly be perfectly fine for me to have the equivalent of six wavemasters on my floor.