I use Metrofax. When I was switching offices and decided to go with an efax, I studied all the options (including the actual eFax brand) and found Metrofax makes the most sense. They give you a pool of 1000 pages a month, in or out (a lot of efax companies screw you on outbounds) for $12.95. They also give the second month automatically free. It has worked incredibly well for nearly a year now, and their customer service on the 3 calls I have had to make (set up, the only slow down I've seen and getting info about international faxing) was exemplary. Only had one day where my faxes were going out slowly (about an hour delay), and it was fixed within 6 hours or so.