Originally Posted by HybridCore
I heard the type of scroll wheel on it is considered the better type of mechanism. I'm also worried about the DA's double click and scroll problem.
The scroll wheel mechanism is a preference, as far as the feel goes; some like firm detents, some like light detents, some like smooth scrolling, some like free-scrolling/spinning (a number of Logitechs feature this). It's hard to argue about this aspect, it's basically different strokes for different folks. What's not arguable, is how a scroll wheel technically performs. If I roll the scroll wheel in a certain direction, that is the only direction it should respond to. Most mice use mechanical rotary switches a.k.a. encoders, that make and break two contacts, creating two signals which are offset in phase, to give the MCU in the mouse a way to differentiate which direction is being scrolled. The problem with these rotary switches, is that they become intermittent over time, due to mechanical wear. When the signals become intermittent, you get intermittent, essentially false, pulses going to the MCU and possibly causing it to count up or down, when it shouldn't. The problem generally only gets worse over time, though using contact cleaner may help. Some mice use optical encoders, Logitech does on most of their mice, and Microsoft does (or at least did) on some of theirs, especially their older ones, CM does on the Spawn. I am sure there are others. An optical encoder works the same way, except it uses a light beam (or pair of light beams, usually LED-sourced) going through a rotating disc with "window" slits in it, built in or connected to the scroll wheel, to a pair of phototransistor receivers to detect the scrolling motion and create the signal pulses. This switching happens electronically, and so is not subject to wear like with mechanical rotary switches. The one saving grace of mechanical rotary switches is that they are cheap and simple. The MCU of the mouse can filter the scroll wheel signals to some extent, to try to reject some of the intermittent signals, but it's more of a crutch used to hide a shortcoming, and not a clean technical solution; an optical encoder is technically better and more reliable in use.
Regarding the DA's supposed double-click problem, that's usually a sign of wear, after long use, or possibly being raged at and abused by the user. The microswitches just wear and eventually become intermittent, leading to false signals, that may be interpreted as clicks (or double clicks). This is not a problem unique to the Deathadder by any means, pretty much any/every mouse on the market can suffer from this. IMO, Omron makes by far the best microswitches on the market, and they generally last a long time. Razer, Logitech, CM, Mionix and many many others are using Omron microswitches for the main buttons, though they might use cheaper alternatives on the less-used buttons. If you get the double-click problem, the easiest thing to do is to get replacement switches; I get the Omron D2FC-F-7N switches for like $2 each on eBay. A few minutes with a soldering iron, and possibly some new mousefeet, and you can be back in business with a like-new mouse. If you're going to the trouble to replace microswitches, do yourself a favor and get Omron switches, even (or especially) if that isn't what was originally installed; IMO, the microswitches from TTC, OTM, and various other no-names just don't hold up as well.