Hi Don....you haven't let us know what sort of experience you have..either jet or total flying hours. If you are contemplating paying for a rating yourself, then I really wouldn't advise the 744...a 744 type rating with no jet hours let alone total hours is about as much use as a chocolate teapot....no-one the world over will hire on the 744 as an FO without over 1000 hours medium jet (or military ) I wouldn't have thought.
With he 320 however in times of plenty, the story is totally different...it is after all the sort of aeroplane that larger carriers will put their sponsored cadets on straight after CPL issue, so even with no hours and a freshly issued licence, with a 320 rating you are definitely employable