I'm looking at buying one, but not really sure how these work or if there are disavantages to the window AC's. I live in Alaska so air conditioners are rare but available. My windows open to the side (not sure the correct name for this), so AC's that sit on the ledge wont work. I'm seriously looking at buying an AC that I can move from room to room but I'm not sure how these work. My rooms are not that big so the range should be ok. Is there anything else that I should look out for? Thanks!