The Logic Off Topic list

I don't get it. What is the advantage of using an Arpegiator? You have so 
much more control using Logic and the pencil - you can see what you are 
doing, you can fine tune to a  much greater extent, and you can save.  
With a keyboard arp, its more of a performance thing it seems.

The same thing about hardware step editors. Its child's play in Logic. 
why bother with an external unit?