I like being able to pick the color and see all the graphics change.
However there aren't enough items in the catalog. I just wanted a simple kitchen object and couldn't find it.
The variety of characters and activities fits perfectly with our needs across multiple projects. I love how easy it is to grab PNGs or SVGs (or import into XD) and also customize the artwork with my own custom primary color. Katerina did a great service to all of us by making these freely available.
Incredibly easy to search and make a selection. I really liked that I can choose a color that fits my branding. I think the only tip I would give would be to display that the .png downloads are not transparent backgrounds.