With SR3 and a reasonably powerful computer, Poser 5 is stable enough from my experience. As ernyoka1 says, it's not a character creation software, but a posing software for figures originally made in other applications. Once in Poser, you can morph these into your liking and in a way create unique characters, but they are still based on a mesh created elsewhere. If that is what you need, there is no real competitor on the market right now (DAZ has something cooking which we know very litte about, despite numerous speculations).