One of the things I like about Avira is that it will always alert me when a suspicious file is found and let me choose whether to ignore it or delete it. I've read that Bitdefender will delete suspicious files without asking.
I found the topic in a discussion in the Bitdefender forum: http://forum.bitdefender.com/index.php?showtopic=27137
At the time, Daniel M. (DanyDan) said that giving users the opportunity to make the decision (about whether to delete or not) was being taken into consideration for Bitdefender 2012. Has this change been implemented?