At the end of the day, both platforms offer the same important data points and if you utilize an ad-blocker, any pesky ad positions or pop-ups are irrelevant.
If you need a free API, the choice is made for you (CoinGecko). If not…
That being said, we recommend forcing yourself to use both websites for a week and then see which one you find yourself organically turning to. Your muscle memory should make the decision for you.
If you truly need a tie breaker, then keep in mind that one site has avoided external funding and outside influence while pledging to stay neutral* and the other is owned by one the largest exchanges in the world.
*Anyone can claim neutrality, but as of right now CoinGecko has been able to avoid any scandals.