IMHO I think you're better off with the service you're currently using (which I suppose to be GoGo6)
Actually I am currently using tb.netassist.ua. I have heard about GoGo6, but AFAIK you need to use their proprietary client, which is not an option for me. I need a plain 6in4 tunnel where the tunnel endpoint can be updated using standard tools.
Updating the endpoint on tunnelbroker.net is a bit easier, because it can be done from a shell script. But when the server sometimes refuse updates, it isn't very helpful that I only have to run a shell script. On tb.netassist.ua the update is done with a html form, which my shell script can fill in, such that I just have to click submit manually.