I'd recommend testing the installation on a backup of this forum, just to make sure everything is working up to scratch, and you experience no bugs/errors when it comes to the real upgrade.
If/when you work out all the kinks, it should be a great upgrade.
Yeah I'm setting everything up on a different domain and database first because there's no chance that everything will work first time.
When I think it's ready for release, I'll just copy the files over to this domain and everything should continue running flawlessly.