Glasses IMO are better, but not necessarily cheaper, in SIN. Back when I was wearing glasses (several years ago), a good pair would cost me S$200-S$350. However, it seemed at the time that the available technology in lenses and frames were so much better than what was available from my optometrist back home. The lenses were predominantly Japanese tech - non-reflective, super-thin (Hoya etc) and the frames were titanium (super light/strong).
A good shop in SIN would be ParisMiki (http://www.parismiki.com.sg) - they have several chains in the city area. There is another huge shop in the Suntec City mall called Yes! If cheap is your thing, you'll have to venture out into the suburbs - take the MRT to Jurong Point (Boon Lay station) or out to Tampines and shop at the neighbourhood mall. All of the optometrists are good - they all have to be licensed - would you expect anything else from SIN?
Malaysia would be cheaper but not by a huge margin. The lenses and frames are imported so the costs are roughly the same.
[This message has been edited by tide (edited 10-29-2003).]