I like that you can block IP addresses at will without having many different plugins running in background or taking up resources. Also being able to create rules for specific types of content (e.g., adult) was very helpful as we've seen lots of malware attacks over time with this type of stuff popping up everywhere! There are some limitations which makes it difficult sometimes but overall it's been great so far. Nothing really - works well enough if used correctly. We have had multiple issues where people were trying to access sites they shouldn't be accessing causing havoc. This has helped us limit what pages those users could see/access within their browser before redirecting them elsewhere when necessary.