RIP software for plotter - what to use ?

I am wondering what RIP software that people use.
I have 2 x Roland 54" solvent printer XC 540, and 2 x Canon IPF 8100 42"

I use posterjet for the canon plotters, and wersaworks for roland.
I works very vell, but the posterjet have many rip errors, so i have been looking to replace it.

I have now a ONYX productionhouse 10, which i VERY slow, but make better print than posterjet.

I also have a wasatch, that are very slow, and not very good print quality.

Most of my prints are 1-20 pcs from .pfd files or jpeg.

Anyone have suggestions for a good rip software ?