If it HAS to be either of them. I would go for 7870
actually no, they are not.What sort of budget you got? Cause they are worlds apart on price.
I think he probably meant 'worlds apart on performance' or 'arent worlds apart on price' - guessing it was a typo.
As for the card, I do agree you should have tried for a 7870, considering recent price falls, but I do have a friend using the Sapphire and he's happy enough with it