I agree with the praise for PreFlight. Good service, picks up right at your car, and very frequent shuttle. MUCH better, and cheaper, than Logan's economy lot.
I think it has been a few months since the price increase. While I have not used it, Logan Express doesn't seem like a great value. Rather expensive parking and bus rates, especially if a family is going. Not a bad option if you are looking to save money, and can be easily dropped off at the bus stop.
Remember, if you are going away for a week or more, and live within 495, a car service both ways is cheaper than driving yourself and parking at the garage. And much more convenient, IMO.