Driver signature protection should only be disabled when one wants to use a driver that is known to be unsigned, and one is will to accept the risk. The Unication driver is signed, so there is no need to do this under normal circumstances. I have not disabled driver signature verification in Windows in years, and the last time was because I was doing something experimental, and understood the consequences. I can't comment on Whistler or any other products, but there is no known issue, that I'm aware of, that requires such a hack for the Unication driver.
I also use Linux on a daily basis (in a professional capacity), and am not a particular fan of Windows, but it is MUCH better than it used to be, in terms of vulnerability to malware, and that's because of things like driver signature verification and user account control. I find ill-informed recommendations to "just turn it off" quite frustrating.