Hi, thanks for all the messages, very, very useful and interesting.Here's some back.
I have noticed that the Luforbec inhaler renders the 'harmonica' note on the spacer ineffective unless you have the suction of a Dyson. It allows an inordinate amount of air past the canister.
This was discovered with the assistance of my precision engineer husband I might add.
Therefore 'some' problems may be due to incorrect inhalation/ too much air/ inaccurate dose in addition to different ingredients.
I think this is an important message.