personally i would go for "MAS" rather than GTS..........unless people know maserati models GTS can be quite generic.
I went with my initials, year of birth and MAS so ended up with GM59 MAS, about £250 but that was 5 years ago so no idea of MAS prices now,.........problem for me is plan to sell the car, as if those that want one of these is not a small enough pool, i now need to find a buyer with the same initials and YOB! LOL
good luck with search