Received my itvn box yesterday and setup took about five minutes, including unpacking. Basically the main configuration I had to do was the router piece for port 554. Once that was done I was able to watch the highest steam with no buffering (so far). Anyway, watched the Czech v Wales game (Welsh were very unlucky but Bellamy, although playing well, missed a few good chances) and had no buffering. Picture quality is pretty decent. It's not HD nor even normal cable quality but at 1000k, not very much lower than regular cable. If I did encounter buffering and had to drop down a level or two to 750k or 500k, then I might not be so happy though.
Generally, I'm only going to be interested in the Liverpool games so as mentioned by other posters this box will probably sit idle quite a lot of the time (there's a lot of MUTV and ChleskiTV stuff). Having said that, if there's a decent game on and we've got 10" of snow outside in January, it may get used a bit more. Still, as an alternative to having to pay $20 per pay-per-view game this seems like a decent deal. The first real test comes next Saturday though.
One comment on itvn support. All my questions on their forums http://www.itvnforums.com/index.php
and when calling have been answered very quickly by US based support. You don't get routed to Bangalore. They're obviously very enthusiatic about this product but I suspect that as a startup type venture, this will either be a great service if it's popular or disappear when they run out of money. I'm hoping and pulling for it to be the former.