It's perfect for a small service business like mine. But my absolute favorite feature is the ability to use the timer to start/stop/start project work on the fly.
I also love that I can run reports so I can see where I am spending most of my time. As a freelance designer every penny counts and the fact that I get all this functionality for free is a huge win.
The ease of tracking consultants time by project and activity through great reporting capabilities.
Occasional failures or loss of service without warning or apparent reason. The desktop application is a little complicated.
One thing it was a bit confusing at the beginning was the total time balance. We couldn’t figure out how to change it or if you wanted to work more than X hours one day, it gave you an error.