After >6 month of Google Voice for my primary line I am a happy camper... I moved more lines over to Google Voice. The enhanced calling features, integration with Android (e.g. Voicemail Widget) etc... would make this a great service even if there was a monthly charge... At the current free rate you can't beat it...
I ported my Vonage line (with an intermediate step of t-mobile prepaid since Google only ports in mobile numbers) over in 4 days. Using an OB110 with Google Voice and am 100% happy. Is it a true landline replacement? Probably not. But I have a cellphone, ooma, sipgate and betamax as a backup and have yet to use either one... It's been a couple of month and so far as I can tell I have 100% uptime... Go google go...
Cortlandt Manor,Westchester,NY
Contract price not specified. 
about 1 days
"Free; Able to port in number; excellent for domestic"
"nothing so far"
"Can't beat the price. It just works for me. Replaced a 25$ month Vonage line"
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