I like that Insightful is pretty easy to use in general. It's straightforward to start a task and then stop it when completed, making its usage very easy. Additionally, Insightful records the start time till and end time. It also takes screenshots and records my screen, which helps in validating and verifying that I'm doing work and what I'm doing.
The approve and reject flow for manual entries is my favorite bit. Someone adds hours for an offline meeting, it sits in pending, and I clear the whole queue with morning coffee.