Running a NH 169 myself, easily teds two 13 foot rows, if the hay needs retedding covers 22'. I'd be careful of "off" brands. A neighbor has a Knerverland (sp?) and from looking closely at it and from my experience as a fabricator at a factory building prototype machines and doing 99% of the repairs now on the farm, I'd say the neighbors Knerverland was crap even when new.
Don't have any experience with Vicon myself and have heard on this site they make a very good disc mower, but does the quality carry over to other equipment? I run NH hay equipment, wouldn't mind owning a NH tractor, but you couldn't give me one of those nightmares that pass for a NH combine.