Excerpt: The Razer Lachesis gaming mouse originally launched in 2007, with a dramatically curved, ambidextrous design and a 4,000dpi sensor. Three years later, Razer has released a new Lachesis, which is not so much a sequel as a refinement of the original. The most important change in Lachesis 2.0 is the 5,600dpi sensor, which puts it on par with other top-end gaming mice.
Pros: Excellent, ergonomic build for people with larger hands; great sensor; ambidextrous design.
Cons: Only two side buttons are really accessible; not great for people with small hands.