This question often gets asked about this time of year...sometimes I wonder if its because people are fishing for help on their personal statements.
Anyways, I'll bite.
Medicine is fascinating to me...but the health care system sucks...its a no win situation. So I wanted a speciatly that was as involved in as many different aspects of medicine as possible....because a little of each specialty is interesting...but I wouldn't want to do internal medicine, surgery, or emergency medicine my whole life....
It's difficult to find a specialty where you can know so much about different fields and still be considered an "expert"...and not have to wait around for lab tests, consults, social issues for your patients like placement, etc.
Radiology IS that specialty....unless you like Pathology I guess...but no thanks. Quick cases, more or less, in all different aspects of medicine, that are good for those who get bored easily...like me.
Staying power....it will always be a field that is interesting, in demand, and gives you time to enjoy things outside of medicine. I doubt I'll be one of those doctors who wants to retire early....I'd get bored anyways.
I'm only a first year resident but its already much better than anything in med school or internship....but yes, I'm a new first year so I have no weekends and no call for 6 months....I might change my tune after December. Typical day involves reading out with attending in the morning, sometimes after a 8am multi-disciplinary conference, then Noon conference/Lunch, then dictating studies in the afternoon, with possible procedures mixed in, then 4pm conferences. Most of the day is all learning, and no scut, unlike internship.
I am a much happier person since starting radiology residency and the next four years should be very enjoyable.