OOOhhhh,

This is for work, not home, that makes a big difference.

Xeon Dual CPU 3.5 GHz? - yes
NVIDIA Quadro FX 4400? - yes (PCIe right?)
Max the RAM available? - 2 Gb or more
Cinema 4D 8.5 upgrade to Cinema 4D 9.1? Can't say
Poser 5 to Poser 6 (when available)? Yes, if it will remain a part of your workflow for some time to come.

If you are pushing your machine on a daily basis, the hardware upgrade makes VERY good business sense. Improved productivity will pay for the cost of the machine in a few months (2-6, depending on your salary, and work "habits"). You could also use your old machine to start a render farm, which will also boost production a great deal (I'd upgrade it to at least 1Gb of RAM though).

The upgrade to Poser 6, I'd say yes, but it's crap shoot right now. To me, the $40 savings over the regular upgrade price make it a no brainer, if you plan to keep Poser as a important part of your tool set. Just make sure everyone understands that it may be a while before Poser 6 is fully integrated into the workflow, since the status of usable plugs for Poser 6 to C4D isn't known right now. The improved render engine in Poser 6 should be justification enough, as you can use it to create high quality demo images without the exporting to C4D. Anything that streamlines workflow is always a plus. Of course Shade LE could prove to be a very valuable addition to your tool set as well.

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