Straight to Gate Logan Express Experience
Took the 8am today for a flight leaving at 11:30.
The location is separate from the usual Logan Express terminal, note that it is across from the AMC Theater on Flutie Pass. Parking is available as is drop off/pick up.
I got there around 7:15 and was checked in, they offered to print my flight boarding pass and gave me a boarding pass for the bus. Then you sit until TSA begins taking everyone for your bus. Process was quick and easy, I think they were still training some folks. You then board a bus and get going. Traffic was moderate for 8:30am and we arrived at Logan around 8:50.
The buses go through the South Cargo Terminal entrance and drop off Delta passengers first, then about 5-10 minutes to get to Jet Blue drop off. I would recommend this highly for anyone who loves aviation, kids, etc. The bus route on airport grounds winds from cargo to terminal A to terminal C, and you're surrounding by planes and equipment the whole way. As an aviation person, it was really interesting to get that view of Logan.
Overall, I would probably do this again on busy travel days, or at off-peak times where traffic is less likely to make you late. I could easily have taken the 9am bus for an 11:30 flight, but I wouldn't recommend the 10am although I would have made it. The process of TSA is about the same time as TSA Precheck.
For $9, it was worth it just for the cool views of the airport.
Edit: For Jetblue you get dropped off around C5-C8, so it can be a hike to your gate.