The SteelSeries 7G is practically the same keyboard as the 6Gv2. The additional $50 you pay for the SteelSeries 7G gets you extra features (two USB ports and an audio passthrough jack), and a detachable hard plastic wrist-rest.
Other than those additions, the keyboard feels roughly identical to the Steel Series 6Gv2, with one significant difference – the Backspace key is the same size as the letter keys, not twice as wide as it is in a standard layout.
Frankly, we're not sure why they did this, since we don't hear many complaints from gamers about the Backspace key getting in the way. We found the smaller key annoying when I used this keyboard for typing (as opposed to gaming).