The o/u combo is a bockbüchsflinte, or as we commonly call them a BBF. Merkel and Kreighoff make them as well as drillings. As an avid grouse hunter I prefer the drilling with its two shotgun barrels.
If I'm deer hunting with my drilling and get into grouse, quail, or chuckar I turn the day, or a portion of it, into a bird hunt.
A BBF can be more accurate on a third, fourth...and so on rifle shot, as they usually just "belly" the rifle barrel as it expands from heat, and they shoot higher.
Drillings tend to walk up to one side or the other when heated up.
Merkels are about the same quality as Sauer. Kreighoffs are better guns.
