8th Ed. Which 40K army do you enjoy collecting and why?

It's funny I am considering life after old world as our club is quite tenuous

I find it interesting that nearly all rankings of supported GW games has 40k at the bottom.

 

I think it's mostly a case where the more you branch out into other tabletop games the more you're likely to see the flaws in vanilla 40k as a game. Likewise if you've been in the hobby-space long enough.