In my rig the HR44 is mounted vertically in a closed cabinet. Many RVs have shallow cabinets and a vertical mount is ideal. With it's RF remote line of sight is not a factor and it can even be in another room. Plus the external brick keeps some heat out of my cabinet. My cabinet is small and hence ventilation is required.
2oldman: For one month I had both the HR24 and HR44 connected (SWM splitter required) and it worked great - 7 channel recording and the HR24 could access the HR44 recordings. This was really a hedge on my part to be sure the HR44 would be OK in the RV.