I'd agree that the Argo/Darky portage is very picturesque, and a nice little walk thru the woods.  Of course the fact that we were almost struck by lightning on that portage keeps it from being my favorite.  A tall pine 75 feet from us took the brunt of the bolt, with bark shot 30 feet in each direction as the sap exploded from the current.

I remember the portages from Joyce to Kash being somewhat difficult, but not awful.  I guess that's because I was going east and generally downhill.  The swamp was pretty tough but looks like they've improved it a little.

My favorite has got to be Prairie Portage, since it's usually the first and last portage that I would use to judge my crews.  Always amazing how a week in the woods changed the teens I took out.