Some people think that rifles designated "AR15" will be a collectors item since it was named in the original ban. I would probably buy one if I could afford it, but I don't have that kind of cash to spend on collectors items, so my rifles will always be designated PCRs, M-15, EM15s and the like. Who knows what AR15 rifle values will do. Look at what happened to Beanie babies, people were paying $2500 for a beanbag toy, now the bottom has dropped out because people realized they have no intrinsic value.
I say if you really want it and can afford it, it's a good price. As an investment, it might be dubious right now because no one can predict what will happen to preban values, Colt or otherwise, if the AWB sunsets. But not everyone buys prebans for investment. My $.02 worth.