Routers don't repeat the signal they broadcast their own so you would have to run cabling to the location of the second WAP and bridge the two. Then you would have two signal points instead of just one then any connecting device would determine which device is broadcasting the strongest signal and switch to that one, so yes its better because it doesn't rebroadcast the signal.
Edit: i misread your post you are asking if the router will be better as a repeater then a repeater. The answer is in the hardware, repeaters are cheaper because they do away with all the other things they don't need that routers have. If the router has a better antenna and its not going to be wired into the main router directly than ya it will most likely do a...