This is the more or less complete Soundtrack, the official OST is mostly cutscene music which is more dramatic than melodic. Would recommend waiting for a sale.
Earned in Blood is the best game in the Brothers In Arms series by far. It has far more engagement and tactical thinking than either of the other games in the series, and although challenging is not unfair to the player.
Yes, it is one of the greatest games of all time. If it plays 'too old' for you, there are many mods to improve the experience and rebalance the game.
