I guess I'm too cheap. My Business DSL internet/phone package came with a dedicated fax line so that is essentially "free". So Brother/Paperport work fine for free. Updox is somewhere between $35-65/month, i.e. $420-780/year. Not much but my fax system isn't overwhelming the office.
One day, maybe I'll actually buy a good fax machine that faxes directly to .pdf files instead of .tif files like Brother but converting them doesn't take that much effort. That's really the big pain. But I've grown addicted/dependent on the Brother e-fax machine/address book.
Updox does look great and I'm sure a lot easier.
What's your cost for paper? The savings in paper alone will pay for our monthly Updox fee. And since we are keeping a dedicated fax machine that saves faxes as pdf files, which are then imported into Updox, we won't use Updox to send/receive faxes keeping our Updox cost at the absolute minimum.