Without exception, I would encourage anyone to avoid an internet service that interferes with the data they’ve requested in this way. Of course, all pages in Singapore are filtered against a blacklist of pornographic/political/hate sites, but aside from that which cannot be helped, no one should pay for anything less than a pure, direct connection.*
Previously: Singapore and Mobile Internet Data Plans
* Singtel offers two internet configuration profiles for mobile phones: One is named IDEAS WAP and the other, IDEAS INTERNET. The former passes through a sort of proxy server (supposedly) optimized for websurfing, while the latter is the direct connection that you should use – it also allows traffic on other ports, such as those needed for FTP, email, P2P, etc.