Pros: 1) Very cost effective, even if you don't make enough calls to avoid the monthly service fee.
2) You can still get a monthly paper statement and pay by check or money order to avoid placing all your personal information on the internet.
Cons: 1) Some data noise and internet or telephone trunk noise in the background on extended weekend calls. This is very minimal, and only to discriminating ears.
2) No dial around number or a vehicle to make calls from another location and have it billed to you account.
3) No "free" toll free number.
Summary: The service has been great for the reasons I mentioned above, as well as the fact the the sign-up process didn't require excess personal information requests. Overall the cost is even less than cell phone plans.