DeskCNC, DeskWinNC, Mach1, EMC etc.... How fast a computer?

Hello:

A recent hard disk crash which had my WIN95/TurboCNC combo has
lead me to realize it's probably time for me to graduate to
modern technology/operating sytems for my CNC work. I love
TurboCNC, but I'm not sure it will ever have cutter compensation
or a graphical interface, or get past a few odd bugs.

Is anyone Experienced with DeskCNC or DeskWinNC? How fast of
a computer is needed to keep feeding the data to the controller
without pauses? I like the idea of software that runs on many
versions of windows, and hardware to offload the real-time
requirements, but is this product working well? Does it have
bugs? I haven't heard much from users. I'm also wondering if
I should get the cheap DeskWinNC now ($200), or get the newer
and more expensive DeskCNC ($300 now, or $350 after 3/1/03)
or wait for the USB controller version, which is still being
beta-tested (but has much better speed, but delivery date
is unknown, as is price.)

I like the idea of Mach1, but after reading it's yahoo group,
I realize it requires a very fast computer, and does have some
bugs.

I've considered trying to get EMC installed (probably
from the BDI CDROM image) but again, I'm not sure how fast
of a computer it takes to put out good performance.

Where should I be investing my time/money? Again, I've loved
TurboCNC, but running in DOS, an old unsupported operating
system, without the ability to easilly share data files across
a network, is a problem.