Masmap overlays very detailed map tiles on top of Google Maps. So if you need a really detailed map of Kuala Lumpur you should use Masmap.
Masmap also includes all the normal Google Map views (map, satellite, hybrid, terrain) and an OpenStreetMap view. However if you use the Masmap view you have access to thousands of interactive points of interest. The POIs include churches, restaurants, hotels, shops etc.
Masmap also includes options to view Panoramio photos on the map and the option to search for a point of interest, a street or an area in Kuala Lumpur.