I use different rules entirely. I use SuperSystem 3rd edition by Four Color Figures. It's a super hero miniature game with a system for designing your own guys, so you can make basically anything. It takes a bit of playing the game and reading it to really get one's head around the way the game works, but once you do, you can make anything in the
40k universe using the design system.
I bought the PDF for $11 from Sabersedge.com
http://www.sabersedge.com/fourcolor.php