I love AntiSpyware, but it has a few short commings. The program is running actively all the time on my PC, but when I double click on it from Windows System Tray to access the main window, its like its starting up for the first time. Its slow and usually takes 5 to 10 mins reach there.
Memory usage is a big issue too, out of all my utility programs, none of them including Norton, Adaware, Spybot use 112 MBs of Memory and 103 MBs memory when the main window is open.
Check out the screenshot from the Windows Task Manager: