Thinking about taking the next step...

I have been working on my current unit for a little over two years now and for some time now I have been considering a change in venue. I work on a Tele stepdown unit right now and there are a couple of transfer options I am considering. I know that we will have several positions opening in our surgical ICU soon and have thought about going there. But I am also very interested in working in the ER, which will also have some open positions in the near future. I have friends on both units who say I would fit in on either unit. Any advice for someone looking for a good learning experience?