Jim,
Too bad your friend didn't know about these forums
The components are almost secondary in importance. The software that creates the interface is where it all has to work. That is where you should start your research.
Nothing that Camsoft uses (as an example) is really proprietory, except their software. Admittedly, there is some close association between what hardware their software can work with, but they have offered to look at integrating drivers for other types of hardware than what I listed.
There are other package deals out there that include motors, I/O cards and relays, software and PC. It may be that this would suit you better. At least you could presume that the package deal supposedly worked somewhere else before you got it.
First you get good, then you get fast. Then grouchiness sets in.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)