How is VoIP better than a landline?

[HSMom]

From the prices I have seen, VoIP is no cheaper than some of the other one-price plans. But maybe I am looking at the wrong companies. We have landline (one price, all of the US and Canada), cell phone, and DSL bundled for $150/month with Verizon's Freedom package. I figure if I had to pay full price on cell and internet, I would be paying $100 anyhow, so how is paying $40 - $50 for VoIP wouldn't really be saving me much. And when I have talked to people who use VoIP, the connection is always weird...sounds like they are talking in a tin can, and there is a delay like there used to be on international calls. So how is VoIP a better deal than a landline? If there is some advantage I am missing, I would love to hear about it!

[Action Man]

Vonage is something like 24.99 and is a flat rate. You also don't have to have phone lines installed.

[HSMom]

But if you already have the phone lines, is it worth it to switch to VoIP? I have been looking at Verizon's VoiceWing, and in their FAQs, this jumped out at me:

VoiceWing does not support traditional 911 or E911 access to emergency services. The limited emergency response service (“Limited Emergency Response Service”) differs in a number of important ways from traditional emergency response services. YOU MUST MAINTAIN AN ALTERNATE MEANS OF REQUESTING EMERGENCY SERVICES. An accurate Service Address is required to route your calls to the closest emergency call center in the event that you dial 9-1-1. VoiceWing will not work if power is out. VoiceWing will not support home security systems and cannot be used with satellite television services. Network congestion or use of data services at the same time as VoiceWing might affect sound quality.

So the service can't handle 911 calls, doesn't work if the power is out, and may not be very good if there is netweork congestion or use of data services at the same time. Sounds like a hassle to me. But maybe I am just dumb enough to pay for convenience and reliability.