Some good posts have been made stating their successful trades. As I mentioned the "buy where you want to stay" philosophy, I should elaborate a bit on why trading was not for me.
Most importantly, my wife is a teacher. My kids are in school. You see where this is going...as we can only travel during the peak (hardest to travel) time.
CLEARLY, exchanging is not a great option for someone in that bucket.
In fact, you can see from those replies that mentioned successful trades - they traded into very good locations, but they were mostly non-peak seasons.
But in addition to that, we have always traveled for 2-3 consecutive weeks per year. Doing this makes exchanges quite a bit more difficult, as ideally you want each exchange to have the same day of the week for arrival. So once you lock in one of those weeks, with, say a Saturday arrival, what do you do when your vacation is approaching and you finally get that offer for your second week, but it has a Sunday arrival? You either need to turn it down and let it roll, or you accept it and pay for a connecting day. Or what if that second week has a Friday arrival. If you accept it, you have adjacent weeks with an overlapping day.
I think exchanging is an EXCELLENT option for people who are retired, or anyone with very flexible travel options, or for those who go for one week stints.
But for a two-income married couple or a couple with kids, exchanging might not be ideal.
My family situation was (and is still) not suited for trading.