Just finished by G-Research Data Intelligence coding challenge! It is 90 minutes long and 4 questions. I completed the first 3 in under half an hour, then spent all my remaining time on the mammoth of the last question.
More details to come (if there is interest :P)
It is an approximate solution question, where you need to impute missing values, and is scored based on how closely you impute the values. Overall it was really interesting! But I did have various wifi-issues which kind of slowed me down!