We didn't take too kindly to the Microsoft SideWinder mouse. While it boasted plenty of features, such as on-the-fly sensitivity adjustment, real-time macro-recording and, let us not forget, vertical(!) 'back' and 'forward' buttons it fell short on the ergonomics front. Sadly its successor, the X5, was little better.
Luckily, with the X6 keyboard, Microsoft managed to save the SideWinder brand some face by being very good. And the X8 mouse proves that to be a trend, rather than an anomaly.
The most obvious reason why the X8 succeeds where its SideWinder predecessors failed is immediately apparent. The X8 sports a much more ergonomic design, eschewing the strange 'hump' of previous models in favour of a smoother design which fits the hand more comfortably. Having used the X8 almost every day for close to a month now, I'm more than pleased with the complete lack of aches and pains in my wrist and hand.
Assisting this improved hand position, the vertically mounted navigation buttons are now flat and angled inwards towards the thumb - a huge improvement over the rounded, protruding examples on the previous SideWinder mice. As a result, it is now possible to use both with only small movements of one's thumb, without repositioning it - something the previous design didn't cater for.
The four-way scroll wheel's metal surface offers plenty of grip and there's a reassuring 'click' while scrolling, although sideways movement feels a tad less secure - certainly enough to cause some annoyance. Three dpi-changing buttons are positioned just behind the scroll wheel. When pressed, these light up temporarily and the sensitivity assigned - via Microsoft's IntelliPoint software - is displayed on the mouse's LCD screen, just above the thumb position.