as I stated in slack, both have their reason to be here and offer different capabilities. I just copy paste what I told you in slack :
both are nice aircraft, with their pros and cons.
747-8 is the neweber aircraft, for Global surely interesting because of its range and ETOPS capabilities. It also has a lot of power, good quality and handles nicely. Negative is its size which limits you on your destination airports and the lack of useful liveries to fly realistic routes with. Also I personally dont like that you can spin the engines up to 120% and climb with overweight in a 45° angle and still accelerate.
A333 ( not the freighter I guess ) is comparable with the 757 and A346. If you have the A346, you wont get a different aircraft basically. However I think those 2 airbusses have a very realistic thrust ration, it makes them more interesting since their power feels a bit more limited. Also it has a lot of useful liveries to fly good routes with. Negative is the not yet updated quality of the aircraft, its not super bad but not up to the standard of the 747.
I personally would get the A333, since its the aircraft you can better use. There are many runways that are long enough for it to take off and land on. But since I´m from AAT I suggest you to get the 748 since we use it as a freighter :wink: