One more outlet for you guys - Kwang Guan Watch and Pen Dealer Pte Ltd at Brash Basah Complex (behind the UOB bank). Their prices are better than WIN's.
The last time I checked a Casio G-Shock with Triple sensor. WIN quoted me $340. Kwang Guan quoted me $315 for the same model with local warranty from Marco. However, I ended up buying another simpler model without Triple Sensor as the owner told me these watches breakdown easily (he is very honest). Most needed servicing within a year. For those of you who are still looking for those classic Casio G-Shock (square face) watch which are Made in Japan, Kwang Guan still stock a few of them but the prices are a bit higher than those regular China or Thailand made ones.
By the way, when you purchase any Casio watch from them and for some reason your watch requires servicing, they will send it to Marco for you.