From zero to hero

Guitar Hero is really hard. And it makes your hand/arm hurt. I've had the new PS2 for just over 2 weeks now and have been playing with my plastic guitar exclusively. I'm getting better but the game is getting harder. I suspect that my inability to play a real guitar is not helping, I just don't have the required strength in my wrist and fingers yet. I finished Elite Beat Agents in 2 weeks, obviously this will take longer (if I ever even get there).
It's awesome fun though!