A monumental waste of time.
Their site is riddled with problems. They offer top x% developers to their customers, but can't produce a decent site for themselves.
I took a programming challenge TWICE (their error).
First time, they evaluated my work as 100% correct. The second time, just 80% correct. No failing test case was ever presented back to me.
Who on Earth codes their site so badly???
In the end, THEY were upset with ME for taking it twice, even though it's THEIR site, under THEIR control.
Also, they don't control the flow through their vetting process. When I solved that problem, it was the first in a set of 2. At the end, they congratulated me for successfully coding up the SECOND problem (which I did no get a chance to touch yet). At this point, their UI flow got stuck and there was no way for me to continue the vetting process other than directly contacting someone from HR via LinkedIn.
When I finally got into a face to face Zoom meeting with one of their developers (the second attempt, because the first was a fiasco), I was faced with a 30 minutes Java or JavaScript challenge. It's the "procedure", I was told. I applied as an iOS developer (I made that abundantly clear throughout my vetting process), I'm no Java guy, so I requested that we end the meeting and the process itself.
Don't waste your time...
