I needed to make three round trips in the same week, and I was able to get at least one leg on every type of train: the new Airos, the Talgos, Amfleets, and as a bonus, the section of the Coast Starlight that follows the same route as the Cascades.
Seats: the big one! All my trips were between 1.5 and 3.5 hours, so I didn't get to test the comfort of riding the longest possible single train trips, which are 6.5 hours between Seattle and Eugene or 8 hours between Portland and Vancouver, BC.
The Airo seats were firm but not uncomfortable. I don't usually recline my seat or try to nap on daytime trips, but the seat recline by scooting forward is definitely less comfortable in exchange for the person in front of you not being able to recline into you/your laptop/your coffee. Another note on napping: the lighting over the seats is not individually controlled. A passenger on my trip complained to the staff that it was too bright to nap, and was told that they're working on that but even the crew can't easily change the brightness, it has to be a software change. The head rest that you can see in the pictures is somewhat adjustable -- there's an inner part that moves up and down, and an outer part that's fixed. I can see the fixed section being uncomfortable for very tall people. The seats aren't much wider than airplane seats, but even in coach they have a buffer space between the seats, as well as two separate arm rests for both passengers. They felt like there would be plenty of space for larger riders, especially because you can leave your own armrest up even if the person next to you has theirs down, giving you some more space to expand into. The tray table was large, and has two different device holders built in for watching things on a tablet or phone. I'd read about the separate cup holders and they were indeed super convenient, so I could have my huge work laptop on the table and still have a separate, secure space for my coffee! I rode in Airo business class on one of my trips, and the seats are the same, main benefit is that you can get a guaranteed solo seat. Since I upgraded, I wasn't able to choose my seat at booking time -- not sure if that's going to be fixed eventually, but the train wasn't full and I ended up being assigned a solo seat. Weirdly, the solo seat side still has two readouts above it for seat availability, one of them is just always green. The conductor was very flexible about letting people in business class change seats.
The poor Talgos are looking and feeling threadbare! I'm not one to complain about whether something is "outdated" but the upholstery is literally peeling in some places. The seats are slightly softer than the Airos, probably because they're old and worn out, but the cushions are thinner so they don't really feel plush at all. The seats are somehow smaller despite the aisles not being wider.
Amfleet cars and seats feel like the generic prototype of "train." The seats are larger than the Talgos, though there's no extra space between them like on the Airos. They're noticeably softer and more plush. The windows are larger than on other trains, giving every seat a better view.
The Coast Starlight is familiar if you've taken any western long distance route. Coach seats have tons of leg room, foot rests, and recline a generous amount.
Restrooms: I didn't do a great job of evaluating these because I hate having to use the restrooms on the train and I didn't actually use the Airo ones. There is only one per car on the Airo, automatic doors, and I overheard the crew talking about how one of them was already out of service because the system said the tank was full.
Physical accessibility: the Airos have noticeably wider aisles. There is space in every car for wheelchair passengers and dedicated wheelchair storage. For people with mobility issues without a wheelchair, the Airos have fewer steps to get into the train while the Amfleets are higher off the ground. I saw an elderly passenger really struggling to get up all the stairs. The Coast Starlight upper level isn't accessible; wheelchair passengers and those who can't climb the stairs book lower level seats on the train and can't move between cars.
Cafe car: all the Cascades trains have the same menu items available. The Airo has "grab and go" store style service for cold food and drinks, where you pick it up yourself and take it to the register to pay. This seemed confusing to a lot of passengers, especially since the menu for what was available grab and go was on the same poster at the register as the things you need to order. Ivar's Clam Chowder is my special train treat, and they also have fresh (pre-made but not frozen) sandwiches that are a real cut above the long distance cafe car. The coffee on my first Airo ride was unpleasant but I don't think that was train dependent lol. I didn't get anything to eat on the Coast Starlight, but as a coach passenger you have access to the cafe below the observation car that has frozen burgers and hot dogs that they'll microwave for you, and sad packaged pastries.
Overall, I'm no longer worried that I'll suffer on a longer trip on the new trains, and there are some nice quality of life upgrades with the space between seats, cupholders, and new dedicated crew office in the cafe car so they are only taking up some of the space there rather than all of it. I love the Talgos in theory but in comparison they feel cramped and desperately in need of new upholstery and deep cleaning. The Airos also felt quieter inside, giving a more peaceful ride, even though they still bounce around quite a bit at higher speeds.
