I was earning a decent amount from Adsense and decided to join Ezoic. Setup was 50/50 (Ezoic 50% while Adsense 50%). Adsense did well compared to Ezoic and we concluded it was because of my Mobile users. I realized that I had more visitors to my site through Google AMP than any other source. The EPMV on AMP was so low and that made me opt out of Ezoic. Yes, it slowed down my site and this was bad for AMP which also takes time to show ads.
Ezoic MIGHT Slow down you site.
Earning is good.
But if you use Nitropack it will be fast.