Doubles are in the area of 15-20K and up. They travel the exact same way as a walmart special with all the other luggage. Few people bring a double with the cost of the gun, and the generic luggage system which does not handle a 20K rifle any differently.
In the 15 years I've been doing this now and the 300+ hunters I have seen only a handful of doubles. None were the same make to my knowlege. Most were not even used, the hunters used the bolt rifles that were scoped most of the time. I got the feeling that the hunters with the doubles brought them along for some type of "christening" of the gun in Africa, and actually killing something with it there.
Doubles have far less flexibilty then a scoped bolt rifle so very few are used today. I know a hunter in Botswana gave his to the PH when his hunt was over years ago. The PH was very proud of the rifle, but it was worth twice the value of his home in town. The rifle was so expensive that nobody he knew would buy it from him in Africa. So here he sat with this 20K rifle he cannot affort to shoot, and cannot sell!
He eventually sold it and got married. But it's use for even a DG PH was not worth him keeping it! From what I have seen I would probably choose a searcy double because they looked very well made and basic, just my style!