I have some general questions about this.
If you have taken this to/from JFK, what did you think? (positive or negative info is fine). How long does the trip take from where you pick it up to JFK? Once you get to JFK, how do you get to your terminal? In my case, JetBlue.
I am trying to decide if this is worth it. Obviously, its cheaper than taking a cab/car service but wondering if its a hassel? Timing is not an issue more $$$.
Please let me know your thoughts.

I thought it was great. I took it from the city to JFK. It takes about 10 minutes to get from Jamaica LIRR station to the airport, where it circles around to all the terminals. You basically take either a lift or escalator down and walk across the street to the terminal. Easy, quick, clean.

How long it takes depends on where you're coming from. You either have to take the LIRR from Penn Sta to Jamaica - about 20 minutes or so - but first you have to get to Penn Sta. Or any one of several subway lines - but again - where would you be getting on.

The key question is - how much luggage will you have. If it's a carry-on or one small rollie (but make sure you're comfy dragging this down the subway stairs if that's your option) you shoud be fine. If you have a large suitcase, a sizeable carry-on and your "personal item" - I would think its way too much trouble.

Luggage will be carry-on only and I will leaving from the LIRR station at Jamaica.

Just a total FYI so there's no confusion when you get to New York:

AirTran is an airline. Doesn't fly to JFK. (Does to LaGuardia and Newark, though!)

AirTrain (note the "i") is the railway from JFK to the New York subways, LIRR, etc.