If you want a clean install the full motion would look the best, Assuming you run the wires in the wall for it. Full motion mounts are not very cheap and will require mounting into the studs since there is much higher stresses on the connection points vs a flat mount which keeps the weight close to the wall instead out out on an arm. With a flat mount if you only have one stud in the area you want to mount too you can still get a very solid install using special toggle bolts behind the drywall.