Escort from Mt. Hagen to Tari?

At the last minute, I am hearing that a group I am going to be traveling with will be driving between Mt. Hagen and Tari under escort (versus flights that were regionally planned). can someone familiar with this practice comment on what the best practices are and who does it well - or who we should be concerned about providing this service. I've read about bandits along the highway, but not really sure what that means - highly organized large groups from a tribal area or a few individuals with knives.