Right Fax vs. Fax Maker

I am working on a proposal to provide networked Fax services for up 700 users. We use Exchange for email so a connector is important. I have looked at RightFax and Fax Maker and both appear to meet our requirements. My question is: does anyone have experience implementing and managing either of these products? If so, what are the pro’s and con’s? Any other alternatives?
Thanks…