With so much choice available I think it is natural to think about alternatives that you might have got even if you love your ring and i also think it is gorgeous. But you know it's easier one day to change a ring into a halo or split shank or twisted shank, or upgrade your diamond - who knows how your taste will evolve over time; what is far harder is to find a guy who shows the kind of touching spontaneity that your fiance bestowed on you. Congrats on your engagement.