The QNX User's Guide says that you can add "set showmode" (no quotes) to $HOME/.exrc so that vi will always show what 
mode you're in. However, this isn't working for me in QNX 7.

http://www.qnx.com/developers/docs/7.0.0/#com.qnx.doc.neutrino.user_guide/topic/editors_Supported.html

My home directory is /home/qnxuser so I created /home/qnxuser/.exrc with one line:
set showmode

When I run vi it doesn't show the mode by default.

I'm running QNX 7 in VirtualBox.