Ewido's speed is more comparable with an anti-virus program as it scans for Trojans and not just spyware: it seems to take about as long as avast!
Of course if you do an on-demand scan as a double check when you download a file it only takes a few seconds!
Thanks for the tip about AntiVir free: I'm trying it now with on-access scanning disabled. The web site has broken links everywhere but I eventually found an old version on Major Geeks. It seems to be a bit slow updating: I think new life forms in other galaxies will have crawled out of the primeval swamp, evolved into sentient life forms, invented the internet and killed themselves by global warming by the time it's finished...
I have also used ClamWin as a double check anti-virus, but after the last update it threw a wobbly and only a system restore would remove it.
Trend Micro Sysclean is another good program to use as a double check.
Although I've scanned with a2, Ewido, ClamWin, Sysclean and several online scanners, I've never found anything that avast! missed.
I probably have my ISP partially to thank for this: whatever anti-virus they use to scan, it seems to catch every virus infested attachment that I get sent even before avast! has a chance to look a it.
Oh, by the way, meanwhile AntiVir update has crashed...