One of my Rolls purchases also had said letter. That is a really nice touch from a company, perhaps more commonplace back then. Maybe modern makers might pick up on this as a nice touch for future legacy.
I also liked reading the names of the places you could get service if you found yourself in, say, Abyssinia and needed something or other you could pop into Hussain & Son on King George Road. It's this sort of historical artefact that tells us so much about life under the British Empire at the time that is all lost once this sort of stuff is consigned to the dump; that detail (okay, made up ... but in line with actual examples) being that a pre-partition presumably Muslim Indian would keep a shop in Africa.
I digress ... but find the period booklets and so on quite fascinating.