My buddy for rescue and DM course was using an Air 2 type device. I hated it for this reason. I had an issue finding the inflator and then working to get the inflator to work. In a real emergency I could see this becoming a big issue. It was enough of a problem that my instructor finally recommended that my buddy get a traditional inflator/octo before continuing to classroom setting with OW students.
Even though its important for a DM to be able to use various devices in am emergency, I could see this device causing problems, especially if the rescuer is not a DM, but just another rescue level diver.
it really gave me an appreciation of the requirement that GUE team me members all have similar equipment.