Easy to use, no technical knowledge required at all! We have been able to send emails in bulk with ease using this software. The interface isn't as intuitive or user friendly for beginners but it's very easy to learn how things work once you get used to them. There are some limitations when sending out large amounts of messages (i'm talking about more than 1k). If your looking into any type of auto responder service then I would definitely recommend checking this one out! You can easily automate campaigns across multiple platforms so there really aren't many downsides other than perhaps being limited by their API limits which will depend entirely upon what plan they provide you with. Sending out sales/marketing automation has never before been easier!!