The Corsair Utility Engine (CUE) is a comprehensive software suite that unifies Corsair Gaming products, including the K70 RGB into one package. The software itself is pretty complex and may leave many scratching their heads, especially because the direct instructions for the CUE are tied in with the K70. For more help with the software, you can read this PDF on the CUE. Something that always puzzles me about 16.8M customisable lighting is how misleading it is. RGB lighting itself rarely achieves more than 256 perceivable colours, however, considering you can adjust brightness and there are two seperate customisable lighting areas, this number can shoot up a little. Nitpicking aside, lighting is a nice feature and there will be many who welcome that little glamour to their mouse.
The ergonomics of the M65 is aided by the curved side, allowing your thumb to rest naturally. Though the M65 is on the larger, heavier side, you shouldn't run into too many issues regardless of your grip style. The precision sniper button has decent resistance so it is rare for you to push unintentionally, which is a good thing considering how large it is. The forward and back buttons are placed in a typical position that is easy to find without thinking, while the highi mass scroll wheel feels sturdy with tactile bumps in each movement. The DPI selection buttons seem a bit backwards compared to the older M65 which had bars to gauge what level has been select, where as on this version, the circular pattern just changes lighting colour.
Tracking was excellent on a standard black mouse mat, white paper, glossy paper of varied colours and on the gloddy wooden finish of the desk. There was no extra curricular movement where the cursor will slide across your screen experienced.
DOTA2 tested those glide pads and mouse clicks as you would expect from an intense MOBA, while Battlefield 4 put the Sniper button to use to test the precision. Overall the performance of the M65 was rock solid and has your back at every point with zero tracking issues.