To be honest, I think bryce's render engine (especially 5) is very good. With the proper care you can really do awesome things with it. So far my experiments in C4D (CE+, yes, I know it's the dark side...) have not bested the bryce render engine except in terms of speed and a bit more control of DOF.

Pass no temptation lightly by, for one never knows when it may pass again!