[CentOS] Bare Metal vs virtualization

Hello to all:

I know this list is generally Linux-only, but I figured I'd try to
gain wisdom from those with hard-core Windows needs, too.

I was recently pricing out a high-end desktop system for a user who
will doing a lot of CAD, Matlab, SolidWorks, and other apps that will
utilize a lot of number crunching and video.

The quote for the desktop (64-bit Vista is likely), which included 12
GB RAM, two 1 TB SATA hard drives, a high-end NVidia 3D video card,
and two Intel quad-core 3.3 Ghz processors, was about $15k.

An approval manager asked if the money could be better spent towards a
cluster for others to use.

This user's needs are for Windows-based apps.    The open question,
then, is can the results the user needs be derived from a high-end
Windows cluster or virtual environment that is multi-user capable and
runs Windows-based apps, or do they need bare metal for true results
and performance?   I awaiting an answer on this from the user.

In the meantime, for those who may have been faced with this, too,
what have you discovered/learned?

Thanks.

Scott