What do you mean, exactly? All I want so say that while targeted attacks are the most difficult to defend against (well, by definition), it is the medium-sophistication-level attacks that cause the most damage (in my experience), just because of their volume. It's not some state-of-the-art APT malware, it's bundles of RATs + generic backdoors/keyloggers packed in SFX archives, that are usually quickly detected by most AVs (provided that AV bases are regularly updated).