Most landlines in the US these days are VoIP and my understanding is that modems work very poorly over VoIP. Before anyone invests in a modem - and in getting a land-line if they don’t have one - be sure to do your research.

Can anyone comment on how well modems work over long-haul connections these days? Even if you have plain ol’ copper wiring to your local telephone company, it’s not gonna be copper wire the whole way.