Thanks all for responses. I actually bought this lens a while ago but did not have the chance to use it yet. Was surprised by its lightness and small size. Agree that for concerts I will have to be very to the subject, not always a possibilty. Hence my question.
Wonder whats the price of the 50mm f1.4 and how much more for the 85mm f1.4.
you may refer to this MO Nikon lens thread. but doesn't mean its selling at this price outside.