The best thing about time kit, I think it's that you can use multiple calendars at once - so if i'm working with my client in one window (and he/she has his own calendar) I don't have to close out of mine just because they want me to do something else.
It would be great if there were more options like this available as well! If anyone needs help setting up their account feel free to message us - we're happy to set things up for you :) We've been using time-kits since last year when our agency launched an internal tool called "timebook". Since then its really made life easier for all parties involved by providing them access to everything through 1 system instead of having 2 separate apps open.