I took the Coastal Starlight SF-LA train this winter with young kids and family and it was an a very nice upgrade to the usual car drive (keeping the littlest one strapped in a car seat for 7 hrs would have been miserable). The views, the conversations, the slower pace, and the adventure / novelty were the best parts and enjoyed by everyone. The price was also much better than flying, as there was a lot of us. Having bathrooms and food and an ability to move around is a huge upgrade on travel with kids. We did business class as the ride was not overnight, but did both legs - 12 hrs each to enjoy the views of the ocean during daytime on the way back. Best part of the trip!
There are some down sides as well:
1. Norovirus - the bathrooms had comical “no touch” stickers by the sink that was definitely not no touch (you had to push the button constantly to get water, even in business class, the economy ones were worse). As a result, we all caught a stomach bug on the way down that played out fully for the kids on the way back. Bring spare clothes and more hygiene products than normal. The upside: we had bathrooms and cleaning materials at our disposal to clean up the mess and we didn’t have to stop anywhere to do it.
2. The business class felt less cramped than coach, and the conversations with strangers were excellent, there were also people on the train that were giving headaches to the train attendants (people sneaking in alcohol and bothering other passengers, people who would not be allowed to fly etc). Normally that’s not an issue, but with little kids on board, we had to be extra careful. On the upside, train is also the best way to travel if you are alone and we met amazing people who were sharing their life story and enjoying a captive audience you wouldn’t get with any other form of travel.
3. The food, while surprisingly good on a first meal (compared to airline food), was also very surprisingly insufficient on the last leg of all of their trips (which SF to LA was). The cafe was emptied out of food by early afternoon, and the dining car REFUSED to serve or even make TOGO food for anyone who was not in a sleeper car. We had a lot of hangry family who was was excited for a meal and ended up eating chips and junk food instead.
4. Because the food provider is a monopoly on the train, they also seemed to short customers of the dining car in what they were paying for with their prix-fix meals, which is your only option on the dining car. Every person pays the same price for a multiple item meal, but we were not told that or offered parts of the meal we were due until we found out and started asking for them on each meal. Since you can’t hop off the train to grab food elsewhere, make sure to bring snacks and alternatives with you.
TLDR: Great with kids, cheaper and less stressful than air or car, but mind your hygiene and bring food backup if you’re not in a sleeper car.