500mm Mirror f6.3 or a 500 f8 fixed telephoto lens

OK, not my lens.  My nieghor is getting into photography.  He's only 14 so he's starting with a T3i and the kit 18 -55mm lens.

He is asking me to look at a vivitar 500mm f6.3 mirror lens and the 500mm f8 telephoto lens

http://www.vivitar.com/products/105/lenses-and-accessories/352/500mr-f63

http://www.vivitar.com/products/105/lenses-and-accessories/1076/500mm-preset

I don't have any expertise with either of these lens.  I know they are a far cry form quality but for a kid learning photography and since they are manual, a good way for him to learn the essentuals.

If he were to get one, which one would you perfer if anyone has experience with these.

--
Focus - Click - Repeat,
http://jbtty.dyndns.org/photo
There is only you and your camera. The limitations in your photography are in yourself, for what we see is what we are. Ernst Haas