What do you like best?
It's very easy to use and has a clean familiar interface, so if you have used other programs like photoshop or illustrator you would find it easy to navigate and use.
You are not stuck with standard looking diagrams, you can customize most of the features and create lots of visual variations to them so you can create your diagrams with very specific details and visual needs.
You can also drag and drop image files into the projects so you can use them as parts of your diagrams which can be huge and detailed as you need since you can zoom in and out without apparent restrictions.
It has quite a lot of features than it appear for a free application.
What do you dislike?
So far maybe the lack of tutorials, but being a simple application you might not need much information to use it, but it would be nice to have.
I would also like to see a few more style choices for fonts and effects customization.
Recommendations to others considering the product
This is a great tool to create diagrams with a high level of customization.
If you are a game developer, this is a great tool to preview or establish the interactions of your games in pre-production.
You can also use it to analyze other game flows and learn from them.
What business problems are you solving with the product? What benefits have you realized?
I'm using it to visualize interactions, key inventory item and npcs placements and scene structures and portal directions for video games (quick prototyping or mockups).
Using yEd has helped me create and preview the flow of the games without using paper, its easier to keep track of and implement, move or remove items, scenes, portals and npcs and it's better to manage instead of paper.