Played both courses while we lived on Sentosa. I preferred Serapong but you can't go wrong. Didn't play either much as they are quite expensive compared to Malaysia. Enjoy and be ready to sweat! Hope you got the early tee times
Nothing to comment golf wise as I've never played there but did visit there 2 years ago. If the golf is anywhere close to the cleanliness of that city, you should be in for a treat.