The Steam Controller is a controller for video games developed by Valve that is designed to work well with PC centric games that normally would only work well with mouse and keyboard controls.
Pro Integrates well with Steam
Considering this is a controller designed by Valve, it should come as no surprise that the integration with Steam is quite good. The user can easily launch into Big Picture mode straight from the controller for ease of use. The controller is plug and play, so there is little to mess around with in order to get going. For those that would like to customize the button layout, Steam allows for this in their settings.
Pro Fully configurable
The control scheme can be freely changed by the user. You can customize what each button and axis does in any specific game.
Key mapping is not limited in any way, so if you have unconventional preferences about what you wish to use some keys for, this controller will not stop you.
Configuration schemes can be saved as templates and then shared with the Steam community. This can sometimes save you the effort of mapping your own keys for every new game you play.
Con Feels cheap
The controller does not have much weight or heft to it and the entire things is made out of light plastic giving it a cheap feel, something akin to a $20 controller for one Android or iOS device. The face buttons on the device are also small, with the shoulder buttons feeling stiff. Overall the lack of attention to detail with the buttons and the overall feel of cheap material gives a sense that this is not the most well designed or thought out controller on the market.
Con Not as accurate as keyboard and mouse
The touchpads on the device are designed to emulate a mouse when playing games, but they are not as accurate and will at times require a lot of swipes in order to just turn a character around or even just look around. This lack of accuracy and delay in how long it takes to get the movement required may be difficult to get used to.
Con Unconventional design
It may be hard for many users to get used to the layout of this controller. The buttons are unconventional and also differently positioned, compared to the regular layout of Xbox and Playstation controllers. In addition, the overall shape of the Steam controller may feel odd at first.