The ability of being able to have an entire business process in one place from initial communication, document sharing through completion with proof receipting is fantastic! Nothing that I can think about right now but this has been working great so far as not much needed changed when we moved over servers at work which makes my life easier since there are some problems between our server setup & ours. We use rapidfax daily across multiple departments within office space - it's extremely helpful in providing documents where all parties involved will be available (as opposed to email) and saving paper/environmentally friendly too! Great way if you're running out of time or just want confirmation quickly regarding paperwork received prior to signing off on them. It helps reduce issues relating to miscommunication by communicating directly rather than having e-mail follow up required after receiving information via phone call. I like the easy to use interface. It's easy to get started and it's also easy to add additional services. I also like that it's very affordable. I wish it supported more languages. I'd like to be able to use it in Spanish as well. I've been using it for sending out documents and invoices. It's very easy to use and I haven't had any issues with it. It's also very affordable.