Unfortunately, for me, the two-car NHV-SPG shuttle varies from 'OK' to non-existent - eg, down. The conductors haven't a clue how to reset it based on my experience with a couple of them. However, a couple years ago, on the Vermonter, the conductor knew exactly where to go in the lounge car and 'fixed' it. So it's hit and miss in my opinion. At least the shuttles are back after 3 years of the stink buggies. I always ride 'uneasy' if I'm not the one driving the car (or bus...I'm not a bus driver). Riding the bus in the winter always had me on the edge of my tiny seat.
Actually, 802.11AC really isn't necessary. BUT...having more channels available onboard for each makes all the difference in the world. Maybe I should burn up some more AGR points and ride the Acela again to see how they have great WiFi.