Flying from LAX to Porto

Are prices roughly equivalent (or, exactly how price-sensitive are you)?

"Economy Comfort" (or whatever term they use) is a step up from plain vanilla Economy (it's not exactly Business class, though, so just a small improvement in comfort - but hey, it's a long flight, everybody likes more comfort).

A 6 hour layover in AMS is a little long IMHO but not a deal-breaker. I'm not a big fan of connecting in CDG, yes, it can be a bit (or more than a little bit) of a hassle. But 3 hours to connect there should be quite adequate, though you may have to do some terminal hopping.

Transavia is fine IME. It's an Air France low-cost carrier partner, not fancy but it'll get you there. The flight within Europe will be pretty short, so lack of economy comfort should be no big deterrent.

Neither option is far superior to the other, so depends on your priorities. If it were me, I'd probably go for the extra comfort seats - it'll possibly give you a fighting chance to get some sleep on the overnight flight.

That’s actually really helpful information, thank you! We are pretty price sensitive. Based on that information you provided, I think we’ll stick with the original plan. Thanks again for the advice!

I just booked a flight - LAX to LIS on American. One stop, a short layover only one hour 10 minutes in Philadelphia. I booked premium economy and my friends are in Main Cabin Extra.