It is pretty strong right now I don't think you can lose. I went to the bank on Christmas Eve to get some cash to put in my DD's stockings for Christmas and thought the exchange was good then so I bought $300 (I'm on the
DDP so I won't need much cash) but now it's even better by a couple of cents. I say go for it, I don't think it will improve that much to make a difference.
Have fun at WDW!