iPhonedo tests the Apple-approved Belkin Car Vent Mount PRO with MagSafe on LA’s bumpy roads. From the video it seems like the initial worries about MagSafe’s magnets being too weak to hold the phone to the mount during a bumpy car ride are overblown. The level of bumpiness on LA roads seem to equal that of Johor, and if it can survive Johor roads, it definitely can survive Singapore roads.
The Belkin Car Vent Mount PRO with MagSafe costs 59 Singapore dollars and you can buy it from the Apple Online Store.