Buying an older discontinued amp can have it's advantages and disadvantages, the cost per output is definately a plus, but an item damaged in shipping can negate that.
Of course, a new amp can also be damaged in shipping, but with the proper shipping box from the factory, less likely to arrive damaged, than someone throwing an amp in a box with some foamy peanuts. There are 'tards' out there that will do this.
Buying from a reputable pro-audio dealer can often be your best bet, regardless if you are buying used or new. They can test an item, rather than some that declare it powers up, and no means of testing... like a pig in a poke.
Dealing with insurance and shipping on a broken item is not my forte. I would rather pay more for new or at least a current model that ships in it's proper carton.
"What the heck was that crashing noise?" Me: "oh, just tossed the shampoo bottles off the shelf on the opposite side of the house. "