DHX air with 888 RC2X?????

I am going to build a DH bike and will have the 888 RC2X up front. Is the DHX air is the right shock for the fork and if it is a good idea to use air on a DH bike. I am looking at the Transition Gran Mal. Simple design, new frame and great price. These guys have done a great job with the Dirtbag so I expect the same for the DH frame. Not sure this is the way I want to go so any input would help.