As far as handling and ergonomics, the AR-15 and AR-10 are brilliantly designed and function the same. Some new shooters may not realize that the AR-10 7.62x51mm rifle actually came first. In fact the AR-10 .308 rifle competed with the FN FAL and M14. In the end, the rifle was downsized into the .223 caliber AR-15, which was a response to the AK-47, but that is history and we are dealing with differences in application today.