However you get much better call and message quality by configuring your online MagicJack account to bypass your old landline equipment and instead "Remote Call FORWARD" all former landline calls to your cell phone!
It only took a week to 'port' the former landline number to a new MagicJack account. The only 'disadvantage' to multiple member households may be that you can only forward to one cell number/voicemail at a time. Still, $3.33/mo is a lot less than $30-$50/mo, right?
My 88 year old father recently sold his home of 55 years. As his family/friends/relatives remembered his landline phone number MUCH better than his cell phone number (and because it was also on all of his accounts), I used the above 'trick' to preserve the number, save money, and still give him crystal clear call reception and voicemail quality!