Its easier with Linux usually because basically everything worth using gets added to $PATH anyway so you don't have to specify the install location - you just write atom or vim in the external editor field and it works - I would say most Linux users looking to use an external application do know what they installed so can just add the word they need.
That being said I really liked the project that spawned this topic where instead of a single application being set it would allow you to pick from a list every time.