1UP USA hands down. In 4 bike configuration it has a weight limit of 50lbs per tray...that's 200lbs worth of bikes you can haul safely and reliably. Secures the bikes by the wheels, no fumbling with straps around wheels or anything that touches your frame.
You are not going to find any 4 bike hitch rack that you won't have to tilt or rotate out of the way so you can drop the tailgate.
You said the "best"....that's it.