Any vest that is ASTM certified and meets BETA Level 3 safety standards. Whether that be the Flex Rider, Charles Owen, Rhodney Powell or the Airowear. They are all designed about the same, with the solid body and the optional shoulder guards.
They all feel the same to me when I put them on, you soon forget they are on. All are just as comfortable to me, as the next. I personally like the Rhodney Powell. That's the one I am going to purchase. I currently have the Flex Rider - I soon forget it is on when I am wearing it.