Even if the cables are free ran (without a conduit) in the ceiling, the gang box will save you some hassle. The holes in the back of the WAP match a standard electrical gang box holes (praise Ruckus designers right here) for a face-plate. That means as long as your gang box is secured in the ceiling, the WAP will never go anywhere (anchors falling out, someone bumping it with a ladder) and mounting it is just a breeze. In addition, aesthetics are way better too as you won't see a cable poking through the ceiling at all.
Thanks. We installed mud rings and it worked out well. I was thrilled that the external Ruckus mount lines up with the mud ring holes -- I was prepared for the hassle of installing screw anchors in the ceiling.
I have done some installations at hotels and they are really rigorous when we are talking about how aesthetic can look the AP installation for obvious reasons, So what we had done is what you are thinking, passing an UTP cable from the switch to the place that we want to put the AP and let the cable just pokes as you said and we just install the mounting bracket, avoiding in this way the use of the gang box because it looks bad aesthetically talking. So in this way basically there is just 1 object that the client or host can see not 2, and in this way the cable is "invisible" for the people too.
My recommendation is to use a good cable and an UTP jack female connector as you will use if you have to put a gang box, so you have to add a short UTP cable; in this way if the UTP cable fails you just have to change a small part and not the entire cable that goes from the switch to the AP, because that can be expensive and inefficient.
We have a similar scenario, where we will be installing R510s using Cat6A. Just wondering if there are others using Cat6A and how they have found to sweep the cable into the device. There is no room for any bend radius. We had planned on using a single gang box, but then to get to the ports, you would need to lay the cable in the little channel, which it doesn't fit, then bend (actually fold) the cable 180 degrees to plug it in. Hope this makes some sense and just looking for suggestions or ideas that others are doing. Thanks