Could you please advise what is the best & more user friendly system between Galileo, Amadeus and Sabre?

For me the user friendly system is Amadeus, while Sabre or most known as Abacus it is so tricky based on my experience, but Sabre is used by many airlines, while Amadeus it is so popular with the travel agencies. And I don't have any idea about Galileo never been used it. 

Hello,

Sabre is more used in Dubai for Ticketing & reservation.