Despite the sheer number of lightweight mice released recently, there is still a market for mice that set different priorities: lots of buttons, extensive customizability both in terms of shape and software, and a construction that is as solid as it is hefty. The Mad Catz R.A.T. 8+ ADV has all of that, and of course, it comes at a price: Even when using the lightest configuration, the R.A.T. 8+ ADV weighs 135 g, and 152 g with all the weights. At the same time, there are people who'll appreciate the weight, and also value the degree of customization allowed for by the R.A.T. 8+ ADV. Not only the length, but also the angle and position of the left-side panel may be adjusted, along with the ability to swap the right-side panel. All of the buttons are of above average quality and can be rebound to one's liking. Another unique feature is the barrel scroll, which is particularly useful for productivity work. The customizability extends to the software, which includes several options seldom seen elsewhere, such as angle tuning. Nice-looking RGB lighting is there, too. Furthermore, PixArt's PMW3389 sensor is implemented flawlessly, although the advertised 2000 Hz polling rate isn't quite real.

In short, the R.A.T. 8+ ADV has a lot of qualities that set it apart from its competition, and even though I'm less pleased about the high weight, it comes down to preference at the end of the day. That said, here's the thing: At $109.99, the R.A.T. 8+ ADV is far from cheap, and for that sort of asking price, I'd expect click latency to be at least decently low. Unfortunately, that is not the case at all. Click latency is just short of 20 ms, which is roughly four times that of an average Logitech mouse. With no ability to adjust this value either, the R.A.T. 8+ ADV simply looks really bad in this regard. Additionally, the cable is very stiff, which is rather disappointing considering what the competition is able to provide in that department these days.

Despite not being a bad mouse overall, the Mad Catz R.A.T. 8+ ADV simply comes across as dated. For comparison, the ASUS ROG Chakram Core too offers lots of buttons and customization, but comes with a much more flexible cable, record-low click latency, and significantly lower weight of 94 g, for $10 less. For $109.99, I simply expect more than what the R.A.T. 8+ ADV is able to offer.