I've always enjoyed that warning at the beginning of the game that you can only use the "official" GHIII guitar or the standard controller. I don't know the price yet. I would assume dealextreme and kaidomain will have them soon. I really don't want to pay $59.99 for an additional official GHIII guitar that still requires a wiimote to work.
I like the extra fret buttons so I can do the hammer-ons right down by the body of the guitar - just like the pros!
Well, if you judge it based on looks alone then it's not great but I wouldn't call it lame. You can already have the Les Paul if you get the original. Less cost, no need for Wiimote -- as long as it holds up for awhile I'll be happy.