The amount of misinformation on these forums regarding other security soft is mind boggling.
I used to be a Avast user but stopped using it because it was quite system intensive if U customised the settings for better detection, also a Avast deep scan took ages to finish, also the silly media player interface at the time was very cheap looking.
I then moved to NOD but after a few missed detections that screwed my PC & the fact that ESET always stacked the database with outdated sigs just before AV tests (AV-Comparatives etc) that were then removed after the testing left a bad taste in my mouth. U would be amazed how many AV companies do that.
I have been using Avira for over 3 years now & it is the lightest AV i have ever used & that is with settings maxed out, a maxed out system scan checks everythin that Avast did but does it a lot quicker.
I have never had any probs with FP's other than nocd exe's for games to save havin the disc in all the time & the fact it labels anythin called keygen as a virus (the only bad point i can find)
All AV's have FP's but whereas Avira mainly does it on setup & downloaded files, Avast & others can knock out a system (seem to recall a Avast FP recently that put system files in the virus chest)
Personally unlike some here i don't hold my AV on a pedastool, to me it is simply a tool that i use to keep my PC safe, maybe folk here should try other security apps first before storming in & slaggin them off.
BaNzI