If you have Poser 5 or less... yes, do the cheat with the sunlight shadow thing. It's probably the only way (apart from adding a hundred or so low-intensity lights pointing into the scene from every angle) to do sunlight in those programs.  It's not how light really works, though, since 8.8% of light will not pass through something that's 100% opaque.

But from P6 onward, I would always recommend that lights be kept to shadow intensity 1.0 wherever possible and some kind of global illumination (IBL or IDL, or both if you have them) to recreate the way that ambient/indirect light will naturally reduce the intensity of the shadows, just as it does in the real world.

As I said, both get the same result. But one way is mimicking reality and the other is just making stuff up as long as the final result looks okay.  I prefer the former.