Fresh toppings aside, gula melaka is the most crucial ingredient in making any ABC/cendol. In fact, it's usually defining factor that separates the good from the great. The quality of gula melaka used here is a class better than other places. It's visibly thicker and instead of melting into the shaved ice, it forms a luscious syrupy glaze.
One cendol I had recently that satisfied my picky taste buds is Sulaiman's cendol. Surprisingly, it is located in Pudu - hidden from the street view at an unassuming corner of this Chinese enclave. If you don't look hard enough, you will probably miss it.