What do you like best?
Excellent visual design, clean and intuitive interface, high usability, elegant fonts, very nice calendar view, funny FAQ, great customer service.
What do you dislike?
No option to add reminders or deadlines, very limited customization, no Android app, no collaboration, rather pricey. Oh, and the markdown for adding links that I keep forgetting - was it round braces for the text and square for the link or the other way round?
Recommendations to others considering the product
For about $3 a month you get a rather basic, but very well designed application for creating and maintaining (to do) lists. You should keep in mind that it was built with this (and only this) purpose in mind. There are no collaboration mechanisms, no deadlines, no social integration. It is basically a well designed online notepad to store your tasks, plans, ideas (dreams, aspirations, ambitions, desires, longings - why does G2 consider word count to be a valid evaluation metric of a review?).
Oh, and there is only an iOS app, although mobile web browsers deal with the web version quite well.
What business problems are you solving with the product? What benefits have you realized?
TeuxDeux is an excellent choice for people who want an app for creating (to-do) lists. It does one thing but does it extremely well. I use it every day. Adding and removing tasks is a breeze, and so is creating additional lists. I use TeuxDeux not only for my weekly to-dos, but also for lists of books, interesting links and articles, ideas, plans etc. I know that there are dedicated apps for that, but having everything in one place appeals to me. It's like a digital organiser.