It’s really not that bad, both interviews are nearly identical, and both sites provide all the study material necessary. If you really want to get sneaky, you an look up the questions in advance. You get a reasonable time to answer, and an unlimited number of attempts. OPS I passed immediately, RED failed me the first time but passed the second. 50-60% of the answers I had no clue about before reading the study material. The worst part is waiting for an interviewer / the queue to get a test, but they’ve got systems to keep your place in queue as well.