The history of the SteelSeries Sensei actually starts back with the SteelSeries Xai which launched back in 2009. The Xai was a huge departure from their previous mouse the Ikari and its new shape was ambidextrous and smaller using some of the popular mice in CS 1.6 like the Intellimouse and feedback from gamers to create the Xai shape. I covered the Xai back then and loved it but it did have some problems. SteelSeries later took that same shape but with an upgraded sensor and an onboard processor and introduced it under a new name, the Sensei. We actually had the first English review of the Sensei https://lanoc.org/review/input-devices/5274-steel-series-sensei all the way back in 2011. I started using the Xai as my main mouse and quickly switched over to the Sensei after its launch and for a solid 8 years used the Sensei or one of the many other variations like the RAW or game or team branded models as my main mouse and in my LAN bag as well.