As you should well know, do something that will keep you interested for the years to come, not what is the latest and greatest. That said, I didn't do a radiology elective till July of year IV, but I had the interest from Gross Anatomy since year I. You get glimpses of radiology in all your electives, but the one thing I learned during third year was that I didn't really enjoy any of the other electives. But when I took my rads elective, I loved it...so, it was kind of a gamble cuz I didn't do the elective till late cuz if I didn't like rads that month, I wouldn't know what else to go into...I'm sure there are people who have changed out of rads...I heard one switched to FP, but most rads residents I've met love their job...most of them are very cool. Not like those jerks who were my seniors and chiefs or malignant interns who love to scut med students from IM or surg 😡. Sorry that was so long. Hope it helped.