Well, here's a little lighting comparison. In the upper left, is the default Poser lighting. The upper right is a "global" set i whipped together in about 10 minutes. Lower left is one of Blackhearted's "ProLuma" global light sets. Lower right is the lights from the "Render Upgrade" As you can see, while my "10 minute hack job" is much better than the default Poser lighting, it doesn't come close to the quality of BH or Shademaster's sets. Would I pay $10 for a single light set? No frickin' way. Would I pay $10 for an entire set of several dozen lightsets with different moods? If they're of the quality of BH's or Shademaster's, yes.
Remember, kids! Napalm is Nature's Toothpaste!