Really poor experience. After a positive first call I was sent an invite to the take home test to complete. There was no time limit or expected time to spend, and the problem was quite open ended and difficult to implement (essentially build one of their main quiz features from a figma design).
After putting in a significant amount of effort, probably close to 2 full days work, with pixel perfect CSS, API, tests, custom hooks, utils, it was not taken forward. The feedback received, while valid, was very nit picky considering the and the fact its a take home test and not a production level PR. I think they should set some expectations and enforce a time limit to ensure it is not wasting both parties side.
I would advise anyone against applying unless you are prepared to put in a weeks worth of work that is both pixel perfect with production level code.