CDN77.com offers custom plans and pricing tailored to sites with high monthly traffic volume, handling over 25 Tbps of data daily and earning a top 20 spot in CDNPerf's rankings. The service is known for its performance, ease of implementation, and customization options for one-person or small teams. However, estimating monthly costs can be challenging for users transferring over 150 TB a month.

The lowest capacity plan starts at $199 a month, which is higher than some budget options like BunnyCDN but includes unlimited HTTPS requests and is contract-free.

In summary, the pros of CDN77.com include high performance, ease of implementation, and customization options. On the other hand, a potential con is the difficulty in estimating costs for users with high monthly data transfer volumes.

Pros:

• Fast Image Delivery: Sirv optimizes images for quick loading, with most requests returned in one millisecond.
• Customization: Users can instantly access images at any size or style, saving development time.
• Deep Image Zoom and 360 Spin Viewers: Enhances customer engagement and trust, leading to increased conversions.
• Dynamic Imaging: Allows for more image control and faster website development.
• Excellent Support: Users praise Sirv for its exceptional customer support, making it stand out from competitors.

Cons:

• Cost Estimation: Users may find it challenging to estimate costs, especially for high data transfer volumes.
• Defer Loading: Some users mention that the lazy loading feature could be smoother for end-users.
• Desktop App: While the web-based service is efficient, some users express a desire for a desktop application.
• Feature Limitations: One user noted that Sirv does not support Augmented Reality product images.

In summary, Sirv.com offers fast image delivery, customization options, and excellent support as its main strengths. However, challenges with cost estimation, certain user experience aspects, the lack of a desktop app, and limitations in supporting specific image features are areas that users have identified as potential drawbacks. 

I have used Cloudflare for DDOS protection but they do have CDN and I plan to explore their CDN someday soon.

I use AWS S3 buckets as the origins for the CDNs that I use. However, their CloudFront CDN is interesting as well.