Well it only took 8 months, but I finally got around to doing something about this, the call quality has gotten too bad with Lingo, plugged in our only phone and did a test call and verified the issue was with Lingo.

So I got the ball rolling by ordering a new cordless phone from Amazon to replace our aged one and let us have both phone lines running so that we'd be able to test voip.ms and have a seamless change over when the time came, and then started reading the 90 page thread that Mark links to above.
About 20 pages into that someone suggests using grabbing a temporary number and using Call Forwarding while transferring from ones old provider - a serious light bulb moment for me, and I checked to see if Lingo offered call forwarding- they did.

Within a few minutes Iwas able to move everything over. I'd ordered and received a new number, I skipped getting a number from my local exchange for one a few towns away that ended in 1984, this was processed and available instantly. A few clicks on the Lingo site and incoming calls were forwarded to the new number. A few more clicks on the voip.ms site, and our out going calls on the voip.ms network show our Lingo phone number. Finishing up with a quick test call to my cell phone to verify things were working correctly. All that is left to do is to have our number ported over.

Initial feed back from SWMBO on sound quality is positive. I'll be calling Ireland tomorrow so we'll see how that goes.

One of the great features that we'll be able to use is CallerID Filtering. While the Do Not Call Registry has done a decent job of reducing the amount of telemarketers we get, we still get some, eg we dropped DirectTV last year,so they call legally call us for I think 18 months to woo us back, but almost always from the same number, that number will soon begetting routed to "I'm sorry, the number you have dialed is not longer in service".

Feature wise, voip.ms has more knobs and dials to play with then any home phone system should, and a lot more then I'll ever need. If you can think it, they probably already offer it.

Now if only I could get a similar deal for our cell phones.