What do you like best?
I've used many time-tracking apps before, but ever since starting at my new company, I've fallen in love with TMetric. It integrates with every tool I use -- Google Docs, Gitlab, Trello. It's unobtrusive and in combination with something like the Pomodoro tracker, it can boost productivity and help you focus.
What do you dislike?
Sometimes it's frustrating to add new time entries. I suppose this could be solved with optimized UX (tooltips?)
Recommendations to others considering the product:
TMetric is extremely easy to use. You can switch tasks in Trello, Google Docs, or any number of integrations supported by TMetric by simply pressing Start Timer from the task or menu (in G Docs). Plus, It's available for all major browsers and OSs (Linux included).
What problems are you solving with the product? What benefits have you realized?
I've noticed better time management. Can clearly see what you spend time on, how you can be more effective, etc.