Thanks for the quick reply Bob.
I actually purchased the 8000. My thought was to keep the old 4700 (4720 essentially since it has a drive in it) and just use it as a NAS only. I figured converting it to an AP would be the best option. This way the setup would use the 4720 to stream NAS files only, while the 8000 would handle everything else to maximize their processors and spread out the load.
Is this worth the trouble do you even think? Should I just pull the drive in the 4720 and put it into a USB 3.0 enclosure and connect it to the 8000, then sell the 4720 or something?