The green car was comfortable with larger and better seats. If you're not nearly sumo-sized then the regular cars are probably fine because it's Japan and so things are clean, orderly and the guests well-behaved anyway. It's worth trying once to see, though I'd recommend upgrading to a Romance Car, such as on the scenic route to Hakaone, as better value for money. If you want to work with a laptop on the train, the green car is definitely nicer.
People being kicked from the green car happened the most on the Narita Express, where all the seats are reserved anyway.
Nice to know, thanks for the input! I will definitely take that to mind.
I also think the Romance Car is better. I haven't been to Hakone with it but there's also a Romance Car going to Kamakura which I've tried, not the green car though. It's definitely something nicer than the regular trains.
A romance car to Kamakura! I'll look out for that one. Our friend lives in Kamakura so we like to go visit.