DavidR
6
Dodging the bullet relates to opening spam/unknown/suspicious email and then clicking on links within it as that is currently the infection method of CryptoLocker.
The web shield should I believe provider greater protection (but you shouldn’t rely on this) than the mail shield. The Web Shield now has incorporated the old Network & Script shields (three shields now combined into one). Whilst viewing the email in your browser also means that you can have browser security based add-ons (firefox and NoScript, etc.).
The MS Outlook is somewhat different as it uses a Plugin which essentially means that avast is working within it, rather than the Mail Shield is outside of your email client trying redirect email through a proxy so that the email can be scanned. So there are lots of differences in how MS Outlook and other clients such as Thunderbird are handled.
I would continue to use web mail, but also curb your curiosity is always advised and simply delete unsolicited/unknown/suspicious emails.
I use MailWasher Pro anti-spam (not free) and all email is monitored against its heuristic anti-spam filters and my own rules; many of my rules catch not just spam but suspect emails. It only downloads a small part of the email which is viewed in text mode and determines if it is spam, etc. I can flag emails for deletion that manage to get past those filters (and edit the filter as required. I can then delete suspect/spam emails from the the email server, I don’t download them for viewing on my system.