Every render engine is different, so expect some crappy pictures when you change.

Render engines often used in the Poser/DAZ-Studio community include Poser's Firefly renderer, 3Delight via DAZ Studio, Vue, Carrara and Bryce. 

If you want a real good rendering engine (and are willing to pay for it), there is VRay. There are some people who use Cinema 4d (which has a very good rendering engine too) to bring their pictures into VRay. Take a look at Gizmee's Gallery if you want to see how this can look if you master that renderer. You may even have more options with it when using it with 3d Studio Max.

Then, threre are free engines like Kerkythea and Pov-Ray. 

The rendering engines used in Hollywood productions usually are Photorealistic Renderman and Mental Ray. Both have a very complete feature set and are fast. Both are very pricy, too, and you will probably need something like 3d Studio Max or Maya to bring your over. 

Again, if you want to change your rendering engine, expect a learning curve. 

A ship in port is safe; but that is not what ships are built for.
Sail out to sea and do new things.
-"Amazing Grace" Hopper

Avatar image of me done by Chidori.