The standard DeathStalker has backlighting and full anti-ghosting. The essential is the most basic, sporting partial anti-ghosting and no backlighting. There are actually four different models of the keyboard, all of them with high quality membrane switches. There aren’t a lot of opportunities to do so, but Razer’s DeathStalker is one of the leading (and few) membrane gaming keyboards on the market. As scissor switch and membrane technology improves, it’s worth reexamining whether that’s still true.
In the world of gaming keyboards, the leading school of though is that mechanical keyboards are the best, and serious gamers shouldn’t waste their time with anything else.