I will tell you that westchester is a very small airport and is extreamly easy to get in and out of, I have parked there long term in the past and remember the cost being reasonable , however that was a few years ago. I usually fly out of there on frequent trips to other places as they had not really offered reasonable direct flights to orlando in the past. With the addition of AIRTRAN and JETBLUE the prices should be consistantly reasonable now.
Its a great airport to fly out of if you can get a good price and I have noticed the prices being just about equal to jkf and laguardia. The sheer fact you dont have to deal with the crowds is worth some extra cost to me, you will be spoiled flying out of there, be warned LOL