One of the programs that I don't plan on discontinuing use of anytime soon - and that's simply because of how effective it turns out to be in the end, and overall, the experience courtesy of the developers. This is one of the programs that have been around for such a long time, and I find it amazing that many years later, it happens to still be at the top (or close in a sense that it's one of the best), leading the antispyware "revolution" between programs, so to speak.
The only thing that takes away from this program is how it tends to bug up on the user at few times - notice the word "few", but that's something that could perhaps be understandable, however not so much given the long-term as far as how long it has been around - more or less, it's an "ambiguous case".
Other than that, Spybot provides the user with a very thorough scan that's sure to pick up even the least suspicious spyware threat that happens to be floating around on your computer, unbeknownst to the user. Spybot includes significant updates every now and then when it's "time", and so far, above all, with other features such as a back-up (recovery) in case should a removal cause serious damage to the computer and the ever-so-unique feature of "Immunize" (basically, what it does is block out particular web activities before it could even get to your computer), there's no reason why one should ever avoid a well-developed program that evidently has had numerous amounts of efforts on the parts of the developers. And not to mention, not one cent comes out of your pocket!