I'm still using DBS Black (see May 18th post); although I do receive regular mail invitations from AMEX to sign-up for the Kris Flyer Gold AMEX - but again, the bonus points only being credited 1/yr is the main deterrent.
Sometimes DBS Black also run a double points (4x) promo for overseas purchases; which is handy if you have business/personal travel around the same time.
Cheers.