Had the Mod 4 done on my HH. I had the bottom entry closed because I wanted to sleep w/out the slit under my legs and have the area under my shoulders and back as smooth as possible. It is more comfortable for me that way. I have another HH side entry and from my experience w/that one felt I could live w/out the bottom entry. As w/most things, there isn't an absolute right way. For me the benefits outweigh the loss.
As for 2QZQ and their work, all I can say is, excellent!!