"Hi I had bad experiences with skype and the likes. Not consistent reception and call quality and not reliable at all. "
Well, Skype is working very well for me, I often make calls to Canada and France and Skype has never let me down.
Skype on iPhone works only if you are not moving but just sitting and talking. However if you are walking outside or a passenger in a car it is not consistent because skype uses Internet connection; wifi or 3G.
However I believe google voice is not voice over as I tested it making calls on edge and works great. I tried it when I was a passenger in a car and was extremely consistent, calls sounded like I was calling from cell phone. With the car on the highway had no problem with call quality and consistency as I would have with skype in this situation.
So I'm wondering if google voice uses cell phone towers because it certainly doesn't sound like voice over.