I have a 2005 Ford short bed with the pin over the axle. The 5er is a 2008 Sundance with the long pin box that is designed for short beds and also has the corners of the nose cap radius in. I don't even get close to my back window, but yes you do have to pay attention. I can't get around to 90 degrees with the trailer, but i can get about 80 degrees.
I have never seen an automatic slider. So some are suggesting that when you start backing in, it "automatically" slides back? Or is it just actuated from inside the cab. Because if you have to get out of the truck, that is not very automatic.