The Scourge/Reaver Wanna-be Conundrum

Well, I guess my title could have been more clever.  That's alright.  Let's instead focus more on the content of this article:  Scourges (and how heavily the word 'conundrum' relies on the 'u' shape in its various forms, lol).

It's not what I'd consider a tactica by any means, but instead a question of why exactly Scourges exist, and what advantage is to be gained by using them competitively game-wise in the stead of Reaver Jetbikes, besides their clearly hard-hitting aesthetic presence. 

Don't get me wrong- it might not be considered an argument for scourges- we're just going to explore the question and their relation to Reavers.