but it sounds as you're running Google voice through PC not with VoIP adapter right?
I did finally try the Groove IP app, and it's actually extremely good quality on my phone, so when I don't want to talk through the computer and I use the phone, it works great. When talking to the U.S. it is very clear with no lag.
if your phone calls stutter or break up it's caused by your wireless connections
I have had two conversations cut off. The quality of the call is consistently good, and then there must be some glitch in the wireless internet because it gets cut off immediately without a progressive deterioration in sound. Finding a new internet carrier for my in-laws is probably out of the question though, so I'll just deal with it.
What is the benefit / difference from Google Voice as to Skype?
Google seems to run a lot leaner, and integrates well with your email and contacts. I have had the same cell number for years, and about a year ago ported it to google voice, and that way, I don't have to port each time I have a new cell plan, which isn't a huge deal, but it's just one less thing to do. You should read their site, but in short, you can put any number you want under your google voice number, and that way will only have to remember one number for any multiple of phones you have, and you can set when you pick up or when it goes to voicemail, (like for a business phone for off hours), etc. I'm sure there are more ways to do this, probably even through skype, it just happens that I have everything under google and so far, it's been very reliable.
Finally, want to have an opinion on using my phone when traveling away from a WIFI signal; I was considering buying this SIM:
OR was going to see if I could get a cheap data only plan in Poland and just run the Groove IP application off of that.
So it turns out that here in Klecina Wroclaw there's not many internet options, and polsat may be the best option. Probably a business opportunity for somebody who wants to lay cable... because even after some troubleshooting, this satellite internet is pretty awful. Slightly better than radio, maybe not better than DSL. I'm running 11.5 mbps when it's good.
Another thing I found that might interest some people traveling, or living abroad, is hidemyass.com, which allows you to locate your ip address any where you like, and in my case, would allow me to use google voice. Turns out, google voice works fine with a Polish IP as well and actually doesn't charge you per minute when calling the U.S. from Poland. But it turns out that the site has some other benefits I didn't think about, such as access to a lot of the sites that are blocked out if your ip is in Europe, such as: tigerdirect.com, ebay.com (doesn't flag auctions with no ship to Europe), nhl.com replays, and netflix.com to name a few.