I've used Lingo for over 3 years now, and have been happy with their service for the most part. When I initially started the service I had intermittent quality issues, times when you dial and nothing happens, and occasional drops. I called support a few times and they seemed quite knowledgeable and were able to resolve most of the issues with some adjustments to the equipment. I had been able to send faxes over the line originally, but have had little luck the last few years. My Dish Network satellite equipment also has not been able to communicate over the line much of the time, but this is no longer an issue for me now that my new receivers have network jacks (Dish charge you more if the equipment is not able to communicate).
The features offered by lingo and some of the other providers can’t be beat. I thing the simultaneous ring is the best feature yet. I only give people my home number, and when they call it rings my home and cell phone at the same time! I can answer on either line as if the were both the same line. Which ever I answer first gets the call and the caller ID information is also shown on my cell phone. I think you can have multiple numbers all get the calls. Lingo also offers an option to have your voicemails emailed to you, another great feature! Lingo does work with phones supporting a message light as well, I have Uniden phones and the message light comes on when I have a voicemail. Lingo of course has all the other features you would expect.
As far as voice quality it is almost always perfect, better then my phone company lines were. I still had occasional glitches, but after getting new equipment just this week it seems they are now gone. About a year ago I called for support and got India, the support person was of no help and the problem resolved it’s self mostly. Just recently I wanted to switch to an annual plan to save a few dollars a month, the support person said I can’t switch. He said I could open a new account, transfer my old Lingo number to the new account, and then cancel the old one. He transferred me and I processed the order. When I called back to see where the phone number transfer was at, I was told “we can’t transfer a lingo number. It was India again and I explained that both tech support and the order taker had said it could be. I said I need to cancel the new number if my number can’t be transferred. He said cancellations is closed, he will have them call me in the following morning. Three days and no call so I called again, sat on hold for 45 minutes and then was transferred to voicemail. I requested a call back and mentioned I had been promised a call back 3 days before. Again, no call back, so I tried to call cancellations 5 times but it would not even transfer through. I called a tech support guy and he also could not get through to them, but said he logged it in the system and I would not be charged if I was late on the cancellation because they didn’t call me back in time. A few days passed and I tried again, got through after 2 minutes on hold. The verified what had been logged and said they CAN transfer the number, but only a special department can do it, they would call me back in two days. Four days later I got a call and the lady said she could transfer my number now, I said ok, and she said she would call me back when it was done. Fifteen minutes later I got the call it was complete and do I want to cancel my old line and second number on the new line. I said yes and she did it all on the spot. I logged in online and verified my new account had my old number and the old account was gone. So yes I had some trouble getting to the right person, but once I did the support was excellent. I know a lot of companies seem to work this way, had the same thing happen with HP, bad support from India, but once you get past that to a real HP employee the support is excellent.
So in closing I would recommend Lingo and I rate them well overall. Unlimited free calls, and all the features you could ever want. I’ve messed with Magic Jack, not bad for the price ($40 start, then 20 a year), but lacks flexibility, features, requires your computer to be on, and is a bit flakey with intermittent quality issues. In contrast I would not recommend Sprint (PCS), worst customer support and accounting errors I’ve ever experienced (Equipment worked well, just billing and customer service was bad). I had more problems with Pacific Bell land lines then I’ve had with my Lingo VoIP service and it’s really nice to keep my service and number through moves! Hope this helps!