I've been using the R.A.T 9 wireless mouse for about two years now, and the buttons etc still respond every time, no spongyness etc. The build quality seems pretty sturdy, this thing has taken some pretty heavy abuse (we're talking its made friends with the wall on some numerous occasions) but after so much use some of the matte plastic coating has started to wear thin on the thumb rest and on the changeable batteries. coating on the feet is still going strong, although there was a hard plastic sticker on the bottom which started peeling away after about a year and a half, peeled it off completely and normality was restored.
I'd say after having owned numerous Razer peripherals, the 9 is the for sure the most comfortable mouse I have owned. Compared to the Razer devices, it fits much better in the hand with the extendable palm rest but more importantly being able to angle out the thumb wing to where i like it. It's alot heavier than most mice I have used however, even when all the additional weights are taken out the back its a beast of a mouse.
Another note on the thumb wing, the precision aim button is the best thing in the world when playing FPS'es. Makes leading targets down a scope much easier than having to use an on the fly DPI button to reduce sensitivity from playing with CQC weapons.
As for any concerns with the wireless connectivity, I've never noticed any input delay, and the battery has never died on me in the middle of shooting. with the little charging dock for the spare battery and the fact its held in by a clip on a spring lever it takes me about 10 ~ 15 seconds to change the battery. You'll always know when to change it, around half an hour to an hour left the lights on the side of the mouse will start blinking at you so you're acutely aware. Average battery life after two years is still around the 8 hours mark in one session just like when i first had it.
