I think you're missing the point. He doesn't want a single light source. He wants his case fully illuminated with no dark spots. A single light source like that is going to cast shadows everywhere, and leave large areas of the case unlit. Besides, those units are bulky. The LED's can be places discreetly to illuminate every area of the case.
You can get brighter LEDS in a small size: Luxeon Lumileds. 120 lumens, anyone? But unfortunately they don't come very cheap...