I would assume that you are wanting to do flight nursing in the U.S. where flights are short hops. I am a flight nurse in northern Canada, and have neither ER or ICU experience. But I do have extensive northern outpost nursing which in my experience has been very important to me in my job. It has allowed me to become flexible in my care and able to "roll with the punches" of northen flight nursing. I find that some of my co-workers that do have ICU experience sometimes are not able to function in certain situations as well as I know they could because they are so dependant on the resources they are used to having in an ICU. But we all work together as a team and draw on each others experiences and knowledge to comprise the finest and highest quality medevac company in our region. Not saying that ICU or ER isn't good experience, it is. But if one is better than the other, I would have to say they aren't, they are both good experiences to have to give you a good foundation when you enter into flight nursing, as I feel with having my northen outpost nursing.