It might be worth a try, depending on if your ISP does any throttling (which likely depends on if they offer their own VOIP service). Here in the Washington DC area, I have Comcast and they have their own dedicated VOIP servers, connected at a higher cable band than the standard ISP service, and according to some of the freebie VOIP quality tests that I have tried, Comcast does throttle or delay packets so that the resulting speech might be too choppy to be acceptable. I'm probably going to try it for a month anyway and see how it is, since my wife calls to Vietnam about $70 a month regularly .
Thank you Ilcomm. I'd like to recommend a service that I recently heard about and exists in Israel (apparently for already 4 years), which lets the costumer call the exterior for a rate of a local call, plus 8.90$ a month.
The service is very comfortable to use, and very cheap to.
The company that gives this service is local 03, and you can also talk to Israel through it in low rates.
Thank you for your help, and I hope I could help some of you.