Most gaming mice will have extra buttons on the side around where your thumb rests, but not many have a big red sniper button. The M65 Pro is a mouse built specifically for first person shooter players, and that tempting button on the side will give your accuracy an extra boost when it's needed. You can find one on Amazon right now for £44.
It didn't quite make our list of best gaming mice, but the Corsair M65 wasn't far off. We like the scroll wheel, we like the low lift off distance, and we like that it's nice and weighty. However, the other thumb buttons are a little too small for our taste, and the driver software leaves much to be desired. If you're looking for an FPS mouse, and are a fan of something bulky in your hand, then the Corsair M65 is a good option. An alternative heavy mouse would be the Logitech G502 Proteus, which is currently £56 on Amazon.
The Corsair M65 Pro has a 12000 DPI sensor, it's made of aluminum, and you can change the weights around, to make it heavier if you wish, or change the center of gravity. You can use the software to configure the buttons, program macros, and change the three zone RGB backlighting configuration around. If you're not a fan of the RGB, the standard M65 is available for a pound cheaper, however the sensor is downgraded to 8200 DPI too.
The price of the Corsair M65 Pro has been fluctuating between £55 and £45 for the past few months, and £44 is the lowest price it's been. It's not quite the "37 percent" saving Amazon says it is, but you do at least get a chunk of money off the normal price.