Ive been saving my grandmothers voicemails for almost 8 years now and when i went to upgrade my phone, i almost fainted when the rep told me they were going to be erased. Thanksfully he put us in touch with a company called http://www.voicemailsforever.com and they ended up much cheaper than the one you suggested above. i think your readers would benefit because they do it for so much less.
Voicemails have been around in one form or another since the beginning telephone communications. This feature still manages to make its way on every smartphone, despite the rate in which technology is evolving. The reason for this is usefulness – you won’t miss any unanswered calls even if your phone is off. The voice messages from your callers will be transferred to your voicemail box and you’ll be able to listen to them at a later date.

In the Phone app , Visual Voicemail (available from select carriers) shows a list of your messages. You can choose which ones to play and delete without listening to all of them. A badge on the Voicemail icon indicates the number of unheard messages.
3 hours agoVisual voicemail. Visual voicemail is direct-access voicemail with a visual interface. Such an interface presents a list of messages for playback, as opposed to the sequential listening required using traditional voicemail, and may include a transcript of each message. In 2007, Apple 's iPhone was the first cell phone promoting this feature.