The car seat is a safer, better alternative to a bassinet. You won't have to remove the child in turbulence (as you're supposed to).
They won't give you both since there's so much competition for those bassinet seats. Too many with lap babies don't get them.
Emirates is one of the few airlines that has bassinets that hold babies bigger than 6 months but at 10 months, no way would mine have laid down. I did put a 12 month old in a Lufthansa bassinet but I spent the whole time keeping him from pitching forward. He wouldn't sleep in it. Got him a seat for the next flight!
It's a myth that you have to force your baby to stay in the seat for the entire flight. That's not possible, comfortable nor logical. It is nice to be able to strap a baby in safely before getting a drink or using the restroom (by contrast, bassinet lap babies should never be left unattended). Mine were way to active to stay in a car seat 11 1/2 hours and when awake, were within my reach, but moving.