Aside from the keyboard, the mouse is the most important device for any serious gamer. However, not everyone is a professional gamer, and not everyone can even tell the difference between different sensitivities. Most of all, not everyone needs to be spending upwards of $100—in some cases even more—on a mouse.
If you're just casual gaming, and mostly using your pointing device for school work or other productivity duties, comfort may be more important than accuracy. For this purpose, most mice will do, even cheap ones. But how cheap can you go?
You'd be surprised. Given that the gaming market is rife with devices that are more than often overpriced, there are plenty of decent options that are cheaper than what would normally be considered "cheap."
Take for example a the Doinshop New Fashion Professional Colorful Backlight mouse (yes, that's what it's actually called). It has a 4000 dpi optical sensor, with six buttons and a clickable scroll-wheel. The DPI is also adjustable between 1200, 2500, 3200, and 4000. On Amazon, it has a decent amount of reviews and a 3.5 star rating. Oh—it also has RGB lighting. How much does all that cost?$4.60.
But what if you went just a bit higher? Could you get an even better mouse?