I've had a great experience with them so far. I'm on their smallest plan, $4.99 (50 pages sent/received months, I think?), and I get my own local number. Admittedly I don't send many faxes, but when I've needed to send or receive them the service has been great. The document editing tools are awesome, as well.

I love using HelloFax for signing and filling out documents. "Faxing" to email is free

Their largest plan is 2000 faxes a month, I do that in a few days.