"The best task manager. Period."
What do you like best?
One of the best parts of Todoist, is that it conforms to how YOU want to use it. If you you are a follower of the Getting Things Done (GTD) methodology, then this will work perfectly for you. If you have your own way of organizing your tasks, then you can make Todoist work that way too! It's extremely flexible and easy to understand. Plus, because it uses natural language it's as as easy as typing (or dictating), "File Quarter 3 report tomorrow" to set up a reminder. Being able to organize things into projects, sub-projects, tasks, and sub-tasks is easy and gives you as much (or as little) detail as you need to be successful in getting things done.
What do you dislike?
I hate to say it, because I know it sounds like a cop out...but I have really nothing bad to say about Todoist. I've been using it for over 4 years now and it is a vast improvement over nearly everything else I've tried. Plus, the price is fair when compared to something like Omnifocus...which is expensive and Apple only.
Recommendations to others considering the product:
Give it a shot. As with any software, read reviews, test it out. The great thing about Todoist is that it's very intuitive. However, if you are a power-user, check out how others use it on Youtube, etc. People do some really cool things and you might end up adding a tip to your skillset.
What problems are you solving with the product? What benefits have you realized?
Staying on top of multiple projects and tasks is hard or an individual. Leading a team and managing every function only compounds the challenge. Using Todoist is a simple and elegant solution to watch over your team, assign tasks and follow-up.