I have a cricket phone for my business. Unlimited local and long distance anytime. Problem is the phone only works in the Buffalo metro area. No roaming.
Price is $50 per month. No contract. Service is adequate, but nowhere near the quality you will get from Verizon. The voice quality does depend on the quality of phone you purchase. I bought the cheap-o. Friends have reported better quality with the higher-end phones.
I tried the VoIP companies but found the technology immature. There were massive hassles just to get my number transfered from the VoIP company back to a copper line provider.
Good Luck!