I own both Shadow and Bonsai. Bonsai has a excellent desktop, and I use it for maintaining lots of information and clippings about personal, non-work interests, and for writing a journal. When I started GTD I wanted to keep my lists in a program with a short list of files, so I could move from one to another easily. I discovered (by reading a post on this site) the clip manager in Shadow. Now I move or copy things from project lists to next action list, from next action to waiting or agendas, etc. I tested linking to the to-do list but the only reason I would have to do that is so the to-dos appeared in Datebk5. The Shadow developer wrote a program (available free on his web site) that makes a list not just launchable (Launcher X does that) but assignable to a hard button. I assigned my next actions list to the to do button.
I agree about the desktop. I used it to get started, and now I use it to set up projects, which have a lot of entries.