Marc:
Generally, I'm pretty picky about the lighting conditions I work in. I'll use ND grads to control contrast in the sky areas as best possible. If the light is too contrasty, that is, there are "hard shadows" all over the scene and I still need to take the shot, I'll use print film &/or bracket (take two sheets, process the first and decide if I need to do something).
As I've been shooting more large format, I find I take fewer pictures and wait for the light a lot longer. Wake up at 4am... sky is socked in with clouds, back to sleep. Hmm... might be good. Get up, drive, hike, "nice sunrise, not photographic"; back to town or out to scout.
As for which print film, one of my shooting buddies has had very good results with the Fuji Pro-160S. You also may want to try Astia. BTW, transparency film generally scans much easier.
For a dynamic range test, I would take your 5D, a Canon film camera and shoot the same scene with you 5D, Velvia, Provia, Astia, and Pro-160S. Bracket the shots in .5 stop increments 1.5 over and 1.5 under. In other words about 7 frames per comp. Get them developed by who you would have the 4x5 film processed by. Places use different C-41 machines and chemistry and E-6 chemistry.
Scan all of them on a film scanner (Canon, Nikon or Imacon). Compare them to the 5D.
For the subjects you shoot, you will now know which film looks like what (for all intensive purposes). In addition, you'll see what over/under exposure does to each slide film.
Hope this helps.
Rich
NGOphotographer