Well I finally got around to picking up a .22lr/20 bore combination gun today off a fella on another forum for not a lot of dollar so will see how useful it actually is in time. Decent condition Savage 24 which has had a gunsmith fettle the trigger to make more user friendly and comes with some see through rings to enable a low mag scope for bunnies, etc and see moving targets for the 20 bore.
Ironically while I was away this weekend I read an article in an old 2007 Sporting Rifle mag reflecting why they are so little used in this country being such a versatile gun. Maybe I'll find out why for myself soon enough!!
Once I get some ammo I'll post up the results with the open sights (which should be fun!!) and then when I get a scope will see the difference,