I love that it can be used by multiple users, so we don’t have to worry about people editing each other's information or having duplicate data in our system; however this is not always an issue when using Google Apps/Gmail accounts as well! It does take some time getting use too but once you do its worth all of those extra hours spent setting up everything correctly before everyone starts working together again after vacation (or just life).
For starters there was no way at first glance how many different types were available within certain categories such as "Email" &"Phone Calls". We also had trouble figuring out what fields would accept dates without us entering them ourselves which could get frustrating if someone else didn't know either since they are constantly adding new features every year. But overall very helpful tool especially while traveling away where sometimes things go missing due to user error etc., being able see who has read email messages helps keep track much easier than trying find info.