The main difficulty that most people have with the UKCAT is finishing on time due to the strict time restrictions. In reality, not many people are going to be able to give proper thought and answer all the questions to the best of their ability. It is important to time yourself strictly during practice, and during the real test, and make sure not to spend too long on a question. People have different strengths and will find certain questions easier, keeping yourself to a strict time schedule will prevent you from running out of time before seeing all of the questions.