when we booked our AA flight a couple of months ago via Miami for December, we chose the earlier departing/arriving flight even though it was showing as a MAX8...my concern wasn't so much flying on the MAX8, but what would AA do with our reservation if they weren't able to fly that aircraft by December...well, a few weeks ago we got a notification our flight changed, and luckily the only thing that changed was the aircraft, now flying on a 738...so it seems to be working out for us