Until someone that has one responds, just looking at the pics on the web site it looks like the passenger slide completely covers the entry door when in. That means you will at least have to open it half-way or so if you can squeeze yourself through a smaller door opening.
My take on slides is that I'm glad I have one, but I'm equally glad I don't have 2. We can squeeze into the bathroom on the AF 990 without opening the slide at all, but if we want to use it for anything else it would be very restrictive using it with the slide in, so stopping for lunch I have to make sure we have room on the passenger side to open it. The dogs won't get in with the slide in.
I love the layout of that Host Cascade though. The sofa in the back is a huge plus. Happy wife, happy life. Does anything else really matter when you are on the road?