Hi there! This is just based on my researches. Hope it helps.
Both of these offers an online service for the website firewall, DDoS protection services, and CDN. As a website owner, you do not want to make your website as a harmful sites. You would not let the attackers to enter your own website. This two can make your website more safer than before. In this discussion, this will make you to decide and you should prioritize three things; Feature, Pricing, and Malware Removal.
Features:
CloudFlare features are known because of their free services. The main purpose of their product is to prevent the hacking attempts of attackers with their Website Application Firewall Product. Their service is to block the incoming suspicious threats before they reach your website. On the other hand,
Sucuri offers a combination of tools and services including Website Firewall, Load Balancing, Malware Cleanup. It will serve as your own protection for your website. They will do something better just to make sure that your website becomes more safer than ever.
Pricing:
Pricing are important to know for customers like us because I think it is a big deal for us. For
CloudFlare, they offer a free CDN services on their consumers. This bundle doesn't include the website application firewall so that your website is not properly protected against to those powerful attackers. In order to protect more your website, you need to apply to their Pro plan which is $20 up to $200/month for a better security. Unlike CloudFlare,
Sucuri doesn't have a free plan. It means that you have to pay for their services, their complete package plan is just $199/year. This includes all securities you need in order to protect your website.
Malware Removal Service:
A short explanation will do this. If you avail the plan that Sucuri offers, it would be a great choice for you compare to the plan that CloudFlare offers. Sucuri bundle will give you the best security you need.
Overall: Sucuri will be the best choice