Residential VOIP voice quality has come a long way in the past few years. You should notice little-to-no difference between your Residential VOIP phone and your land line phone. But here are a few tips if you're concerned about voice quality on your Residential VOIP line:
* Use a good-quality phone. You can buy a special VOIP phone or use a standard phone with an adaptor. But a cheap phone is going to sound cheap, no matter what service you use.
* Get a service with a tryout period/money-back guarantee. This way, if it turns out you don't like the voice quality of your Residential VOIP line, you won't be stuck in a contract or lose a lot of money.