I used this service four times and all four times the driver was a little late but I always made it to the JFK airport way before I actually needed to be there. It does get a bit long - picking up or dropping people off on the way, but the price is not too bad so I guess it makes sense to grin and bear it.
Overall this is a reliable company, I keep using them over and over again. The only thing I am not particularly happy about is their pick-up times being spaced out across chunks of time where you have either just missed the shuttle or have to wait another two hours for the next one. That is not so great, but other than that, they are pretty good.
Pros: Less expensive than a taxi, less hassle than a train
Cons: Sometimes rides are too long
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