Applied for the job last year, didn't make it, but made a good enough impression to be asked to interview again a few months ago. Unfortunately I didn't have time to devote to the interview process (being on vacation when they reached out was bad timing).
The interview process is involved and difficult - there are work personality assessments and work samples involved. However, it benefitted me in that I took the leg work from that and added it to my resume/portfolio. Also, I think it's a way for Kitces to makes sure they hire the right person.
I ultimately was not selected the first time because I didn't have enough experience. Overall, though, I have a positive impression of the company and the interview process.