This is their best release, even though I love all their stuff. Tommorrowland, the one before this is probably my least played of their four, but even that is great. I think that if they were a European band and not from Australia, they would be bigger.
You are right, they have not reinvented the wheel, but their take on trad/power metal is great.
The two guitar players work so well together that I hold them in the higher echelon of guitar duos amongst the all time greats. Their interplay is amazing. And the singer John has great pipes that has a nice raspy touch.