I understand your frustration with Backblaze if it didn't work as expected, especially in terms of backing up USB flash drives. Zoolz indeed offers a free 100GB service that works well for many users.
If you are looking for alternative online backup options or have specific backup requirements, it's good to explore different services to find one that best suits your needs. Zoolz appears to have impressed you, so continuing with a service that meets your expectations is essential for peace of mind and data security.
Always choose a backup solution that not only meets your capacity requirements but also offers a user-friendly interface and reliability to ensure your data is safe and easily recoverable when needed.