I mostly used Coinmarketcap before as my main reference for any coin information.

But as of now, my preference now switches to Coingecko. I don't know the specific reason but maybe I found the site more user-friendly and organized with a simple layout. I'm not saying CMC is not like that but it's just that, I'm now used to referring to Coingecko most.

Regardless, both sites are good references. It's just a matter of self-preferences.