From 4x5" to 11x14" drum scan and LightJet/Lambda might not be that much of an advantage, compared to a well made Ciba or Fuji R print. I think you would see a bigger quality advantage from 4x5" with a digital process if you want to go to 20x30" or larger. There is also a cost advantage in digital if you want reprints in the future, where the lab can just run them off quickly from the finished file with the major portion of the labor having already been done and without concern about damage to the original film.