I was lucky in the fact that my first double came with 3 sets of barrels 7x65R, 9.3x74R and 470. All 3 sets had detachable scope mounts. It is a Krieghoff so it has a cocking & decocking safety. Having only hunted with the 2 smaller calibers I would recommend them as a first time starter double in a minute.
The 7x65R and the 9.3X74R are as versital as you can get. It will cover anything but DG. They are a lot of fun to shoot. The cocking safety was easy to get used to and I seem to have no problem with it. I'm confident to hunt with my son using it and we all know how kids minds and safety issues can sometimes wander.
I believe from these forums and questions like these I made the best decision for my area, hunting expectations and ability.