A morse code key collection vs a collection of morse code keys

Okay – what is the difference?  In my view a key collection is acquiring keys to display with a possible focus on a certain manufacturer or maybe a period in the history of morse code.  A collection of keys has the focus of acquiring various keys to use on the air.  I fit into the collection of keys group.  I am about done with my collection of keys.  However, I would like one more.  Either a J-36 or a McElory bug key.  I may never purchase one as they tend to be expensive and I am not knowledgeable enough to know how many of the key’s components are authentic.