I tested many, its very easy to setup, great customer support. Add it to your signature file, make sure you update your own calendar and it does the rest for you. Very accurate, big time saver. I book demos worldwide selling construction software, 14,000 live chats in a year, 2,221 demos in 4 years, so any smart tool that allows me to do the work of 3 people is welcome. Review collected by and hosted on G2.com.