We've been using CallCentric with an Obihai VoIP ATA for 2-1/2 years. Perhaps a bit challenging for the tech-impaired to get set up, but it's worked nearly flawlessly in all respects the whole time.

One advantage to going that way was, once I was satisfied everything was working correctly, all I had to do was pull the internal phone wiring off the customer side of the phone company's NID (Network Interface Device) and plug the Obi ATA into a nearby phone jack. Voilà: All the wired phones in the house worked just like they always have--except now the ones that supported two lines had two lines.

Being as my wife has friends and family literally just about all over the planet, we have a Cadillac plan that costs $22/mo. But, still: That's less than half what our "at&t" landline was costing and with several times the features--incl. two lines.

I got my Ooma today from Amazon.
I followed the instructions and the Ooma light has been flashing purple with the occasional blue flash in there.
Setup card says flashing purple is downloading a software upgrade. Been going for about 30 minutes now.
30 minutes a usual download time people were seeing?

I completely forgot to update this. I have had the Ooma for over two weeks now. Although it acted a little "wonky" at first, it settled down and does what it's supposed to. I hooked it directly to the modem and didn't bother with "porting" the old number, just got a new one. I never did get the handset to work, however.

Well it appears to be up and running.
I just did the number port option. It says 3-4 weeks it could take and that service needs to be on the whole time.
My magicjack runs out on 12-31 so hopefully it will be ported before that goes dark.

One thing with MagicJack you did not dial a 1 before the area code. So I will have to get used to that.