I still prefer Poser 4, but my libraries are too large to use it anymore. Poser 5 is nice, but I find even the P4 renderer takes too long in P5. I'd go back if P4 could handle subfolders and large libraries. I like P5's ability to handle multiple runtimes.

Poser 2, 3, 4, 5, 6, 7, 8, 9, 10, Pro 2014, 11, 11 Pro