All I can tell you from my experience is I use Eset on-demand scanning once in a while. I would use it more but it is very slow. For example their default scan on my x64 computers takes 35 - 40 minutes which is maybe 4 times slower than avast! Quick Scan and about 75% slower than it takes avast! to scan my entire internal HDD.

Eset has found a couple of items that avast! has missed but I prefer to use Stinger over Eset even though Stinger is slower but it has been more effective in finding bad stuff especially in MSFT backup image files.