i have tested a couple of anti-spyware
1. anti-spyware intergrate inside zone alarm pro
2. ms antispyware
3. webroot spysweeper
4. spybot s&d
5. adware personal SE

ok, i will rate according to the no. beside from
my favourite --------------------------> the worst i think
4--->5--->3--->2---->1

Why adware personal SE is my top choice :
It is able to scan advertisement cookies which other fail to do so... For example doubleclick.net which is installed when you surf friendster. However the update server is problem matic. And it as some additional add on like startup checker, uninstaller, and some basic shredder. Great for something which is free

Next adware personal SE,
2nd best, i dont enable real time protection as i wont sacrifise performance for security for my pc. The scanning is reasonably fast. Hmm , the problem is i always get "zero" spyware result from "most of the scan.

webroot spysweeper,
works nice on everything, except, very slow scan(too detail maybe), and resources hungry. Can cause "lag" when try to open out the windows minised on the customisation status tab

Ms anti-spyware,
since the 1st day i install til today, still zero result. after 3 months of usage. i dont believe that my pc is "that clean"

zone alarm antispyware,
crap, disabled

forget to mention too ewido suitware is very comprehensive, but suck up lotsa memory