I ended up finding and buying a New MX-700 on EBay for ~$120.
I had no trouble downloading the software from HTM.
They are popping up on EBay used and new fairly often.
In fact there are even a few MX-200's there now for a steal.

I like the more sophisticated programming capabilities of the MX-700 but I have to say i don't like the difference in the layout of the transport controls. It'll take me a little while to get used to it

All in all it's a definite upgrade. The 700 is much more visitor friendly.
Macros are much faster and the IR output strength seems much more powerful, but it could be that my old MX-500 was just getting weaker.