I am another CED owner living on the other part of the world.
Here are shooters using all brands of chronos and I can understand the pros and cons of the main models.
The CED is one of the most precise and on the opinion of most of us it is the real alternative to the Oheler.
Naturally, as a precise instruments it needs an accurate setting before shooting: I own a Model I and had no problem following the instructions exactly and shooting at 6-7'' from the sensors with all calibers.
Surely it is sensitive to the light conditions, as all the other chronos. This depends on the kind of sensors used, based on the same principle of working.
The infrared lighting is surely an improvement for lessening that sensitivity, in addition to the possibility of working with poor light conditions.