Heck yeah, I think you did good. How much more would it have weighed on your mind if you didn't get it? And really in the scheme of things how much is $400 in today's world? I also like to figure that in a few years you'll be able to get a better return on your $400 than if it sat in the bank.
But then again, I also bought a 2 inch 10 -5, that I really didn't need either, and I'm looking for a 29-2. But also I don't have any regrets.

Tom