I've always used it with a VPN. The setup of it changed a bit last season - site redesign, new web player and stuff. For the first week or two there were problems using a VPN but it got sorted out and I've used it since. I don't know how it would work buying it in North America then using a VPN to get around it, but based on my experience I think it would work. In seasons gone past when the odd game would be blacked out in the UK (and in the playoffs when they all were) I used to set my VPN to Portugal and never had any problems accessing them.
I have a read about the terrible state of things in North America here every once in a while and I'm just constantly amazed. I think NHL TV with a VPN would work if you're in North America, but I don't know for certain.