okay, I've had both G500 and DA for a long time, here is what it comes down to:
1. shape. I've found the G500 to be a little more comfortable in my hands, better contour for my ring finger/pinkie part, go to your local bestbuy and try for yourself. To me, the shape and size of a mouse is everything, who gives a **** about what kinda sensor does it use afterall?
2. Mousepad. The deathadder has very small mouse feet, as a result, it might scrape against some softer cloth pads, in my case it was the Qck+ and Qck mass, resulting excessive, unwanted friction. (think about sticking your fingernail into the soft texture of the pad and drag it along) It may sound like a big problem but after you try the DA on a metal pad you'll know what I'm talking about, it absolutely flies on my old SX. The G500 has bigger mouse feet and therefore doesn't suffer from this problem.
hope it helps.
