I had been a paramedic and flight medic and Navy corpsman before/during nursing school. Esteemed colleague
@TLDR20 was a 18D. So our perspectives are skewed if not legit. I also went to the ED after a few years in a SICU, and work with ED RNs now (well, I also work with SICU RNs).
Having ED experience as an extern will be super helpful before going into the ED as a RN after graduation because you'll have a better grasp on the reality vs perception. Critical care patients in the ED are about 5% of the ED population. Not saying a lot aren't sick or won't be admitted, they just aren't critical care patients.
I will also say the new grads in the ED who think it's smooth sailing after a short time don't know what they don't know and have the highest number of errors and sentinel events. Just make sure you go in with your eyes open and ego in check so you don't kill someone.