Reality is for anyone interested in creating photorealistic 3D art using physically accurate materials based on real-world properties.  I've used Reality 3 exclusively since it was released last year.

The single biggest advantage it offers over Firefly is being able to create and edit physically accurate materials with just a few clicks instead of spending months or years learning how to master Poser's Material Room to achieve similar effects.

In other words, imagine bagginsbill's knowledge and experience programmed into a $30 plugin, and you've got Reality.