Likewise, I recommend 1-2 yrs in ED and transfer to ICU. You need the experience of working with critically ill adults. Things can be boring in the cath lab doing scheduled cases. Also, your emergency patients can come in with cardiogenic shock..need a intraaortic balloon pump placed, Its important to be able to mix drips while gathering equipment if necessary. Its a great place to work, but my ER junkies get bored and ICU nurses don't like the call requirement.
Best wishes for your success,