Picked this game up used thanks to a gift card I had (along with DJ Hero 2). I knew the complaints coming in, so I expected it to be awful. I was at least glad I could see right away why so many people hated this game.
1. The calibration is terrible. And the method they give you for calibrating is pathetic, expecting human eyes to match up sight and sound in 5ms increments.
2. To make matters worse, the game deals with "gradations of right", a la DDR. You can play a note "perfect" or play a note "good". Ironically, if you want a good score (as in even more than one seal...aka star), playing "good" notes won't help you. For a game like this, that's a terrible idea. You should either hit the note or miss it. With this kind of system, your calibration is the difference in "perfect" and "good". And thanks to my first point, that doesn't make things easy or very fun.
Thankfully, you CAN program your calibration manually. So, as a last ditch effort to make this game playable, I decided to look up my RB3 calibration numbers and just plug them into the game. Amazingly, this worked better than anything and allowed me to play on "Master" level and get 5 seals and the 200 note streak achievement on my first song.
I still doubt this will make Power Gig a great game, but for anyone who tried it once and got frustrated by missed notes or an abundance of "good" notes, try plugging in your RB calibration numbers and see what you think.