I think is what is meant by approimation, but still more is better than few I believe. Found the bit you are looking for in part one there then.
The test victim:
A customers XP computer loaded with nasties. It had very slow performance even after msconfig's startup was cleared. Popups reared their ugly head before IE was even opened. Trying to use IE was a lesson in futility. Since the customer was on vacation, I took the opportunity to run some head to head tests with various malware removal programs.
The computer had numerous toolbars, websearches, and a couple of "bad" P2P programs in the Add/Remove list. For testing purposes, these programs were not uninstalled. Preparation of the computer consisted of clearing msconfig's startup, and running Ccleaner.
All free or trial versions of Ad-Aware SE, Spybot Search and Destroy, BitDefender's Antispyware, Nod32, Trend's spyware scan, and Ewido Antimalware. I wanted to include Windows Defender, but it requires SP2 and the computer didn't have it.
All programs were installed and updated in safe mode with networking. Scans were run in safe mode only. I won't list particular malware that every one of the scanners found.
Booked Space, Dialer, Dyfuca, WebEnhancer, win32.welchia, My Websearch, win32.trojan.downloader, Target Saver, VX2, Win32 trojan.DNSchanger, Zestyfind.
180 solutions, casclient, max search, my web search, network monitor, smitfraud, Max Search, Zesty Find, Dyfuca.
Backdoor Codbot, Backdoor Aimbot, Adware Agent, Hotbar, plus four various Trojans.
Win32 Dialer, Web Enhancer, Creazione, Win32.Nachi Worm, plus 16 Various Trojans.
Avenue Media, Hot Bar, SideFind, Purity Scan, Web Enhancer, Target Saver, Avenue Media, Ad Clicker, plus five various Trojans.
Backdoor Aimbot, Dropper Agent, Hijacker Small, Worm.Welchia, Backdoor Codbot, Backdoor Rbot, Downloader.Smallbuy, Hijacker.VB, Zesty Find, Dyfuca, Adware URL, Web Enhancer, Surfside, hotbar, Dropper Agent Downloader, TS Update, Dropper.Small, Adware Agent, Not.A.Virus, Downloader ISTbar, Adware Internet Optimizer, Downloader.VB, Downloader Small Buy, Downloader.Adload, plus 19 various Trojans.
BitDefender was a huge disappointment. It seems that the makers of BitDefender AntiSpyware are still stuck in the now extinct "virus days".
Ad-Aware and Spybot were both decent at detecting general spyware and adware, but very poor at anything more serious. Trend wasn't much better other than the four trojans it found.
NOD32 was poor at detecting adware/spyware, but extremely good at finding the trojans.
Ewido was simply incredible. It reigned supreme in detecting both general spyware/adware, as well as trojans, backdoors, and downloaders.
For the actual cleaning, I ran Hijack this first, just to see what it showed. Needless to say, it was a log from malware [bleep]. I ignored it and uninstalled about five malware causing programs. I then ran Ad-Aware, Spybot, NOD, and finished up with Ewido. HijackThis now only showed 3 rogue entries (2 URL search hooks and 1 missing file)...fixed that. On reboot, all was fine. Further scans and observations showed no malware present.