The AM 787 beds are really quite nice, actually - I found them to be a little better for sleeping than Delta's lie flats because they don't taper at the footwell. I'm 6'3" and was able to fully stretch out without being cramped. Don't worry - they are true lie flats, and don't feel small in the slightest.

If you're traveling alone, make sure to pick a seat in the middle section, though - the window seat groups don't have direct aisle access.

Be really vigilant that they don't swap equipment to a 777 on you - that happened to half of my trip and I ended up in a middle seat. It worked out well enough because the guy next to me slept the whole flight, so the seat might as well have been blocked - but definitely not what I expected when I made the booking.

I also STRONGLY recommend never checking in at a kiosk for AM flights departing the US if you're not traveling on an 006 ticket. Delta does their ground handling at some stations - similar to some KLM flights - and the Delta system dropped all of our seat assignments for the folks in our party who used the kiosk. The passengers who checked in with a human at the Sky Priority counter were fine - it was just a problem with the automated system. We were bounced around literally eight different people between SFO and MEX, none of whom were able to fix the problem...

Overall I really enjoyed flying AeroMexico and would do it again. The catering is best out of MEX and much worse from outstations - the catering ex-EZE was really pretty bad - but the crew were excellent and the 787 experience was very solid.