Welcome Pui! What type of vape do you prefer? I find that bottom coils are a much cooler vape than top coils, which appears to be dominated by Kanger as KerryK has shown you there. Personally, I prefer DCT wick clearos which perform better on VW mods. I would definitely suggest upgrading to a VW mod where you can have a lot more control over your quality of vape, but its all in what you are looking for out of your experience.