While I know I may not be the truest fan of Metallica, and this game is therefore not geared towards me, I tried it with an open mind. My initial impression of the game was pretty surprising, as I was not a fan of GH:WT. Neversoft have managed to make some good improvements to the game mechanics that I desperately wanted so I could finally enjoy it as much as RB/RB2. Sadly, I soon realized that while these mechanics were indeed a good step forward this game lacks much of the musical soul that I associate with the RB series (and I know that I have some bias coming into this loving the Harmonix touch to their games).
In finishing all of the careers completely, I simply could not get out of my mind the fact that I would love to be able to take some of these songs into GH:WT ala RB into RB2. Halfway through my trek through the game, I was bored to tears and I found myself fighting the urge to quit. Metallica fatigue set in, and this is the one thing that I was hoping would not happen. I am sure there are those out there that love these type of songs for the challenge of Expert or Expert+ (on the drums), they quickly devolved into saving my star power for the inevitable solo in the middle and end of the song and was quickly reminded why I do not like the vast majority of early Metallica songs (early 80's Metallica).
Something needs to change here with their formula, and I hope they can find a truly inventive way to approach the single band one-off, as I think it could have some potential. Sadly, I don't think this is going to happen, but I will continue to hold out hope.