Newbieone, it's targeted for mmo peeps, not rts
. as far as a size comparison...600 seems a bit bulkier. My thumb sits in the exact same place as it did on the naga. I have a problem with the same row of buttons on both (ones closest to wrist). If you have the razer epic, it's equivalent to that, with the largest grip attachment on the right side. I found that I was pressing the g shift button accidentally too much. The other problem with using that mouse button for g shift is that it stops all current mouse functions to make the second layer available. For example, I'm using the right mouse button to turn in wow. I use g shift to execute a command on the second layer and it stops my turning and to continue to turn I have to release the right mouse button and press it again to continue to mouse turn. Primarily a problem in pvp on mmos, but still annoying. I'll have to see if there's a way to make gshift not effect the regular buttons. Until then, I've disabled the button.
Overall, feels better to me than the naga. Fills my hand so I'm not dragging fingers on my mouse pad like I am with the naga. Movement and acceleration/prediction feels much smoother than the naga as well, at least to me. Who knows. Might just be the new toy effect...liking it better than everything else until something gets to you enough to make you wanna smash it hehe.