If I've got my numbers right, that's 6.4 (still air) miles per imperial gallon at max range cruise - not really the future, is it?
Surely a turboprop would be able to generate a massive saving over this at 240KTAS and FL250?
This VLJ stuff just doesn't make much sense to me. Using a jet for international(?) travel, you choose FL300+ and near transonic or it's not worth bothering. What am I missing?