Avast Free is simple basic AV with no antispyware.
Any feedback on Bitdefender Free AV and Avira Free?
Avast incorporates Antivirus+Antispyware engine for many years, and the PUP detection can be enabled using the First run wizard after installing the latest 2015 version. On modern hardware, they offer avast! NG which requires Hardware Virtualisation, so unless you're running an old PC, then you cannot say Avast is a simple AV. Hardened Mode offers default deny to any non-whitelisted programs, when set to Aggressive.
>> Avast may offer Google Chrome and/or Google Toolbar, and Dropbox software.
If you're afraid of Adware/Spyware from getting on your PC, try out Unchecky.com which will automatically de-select any promotional software and run silently in the background. It will warn you, when you try and install any third-party toolbars etc.
Bitdefender Free Antivirus requires a Bitdefender account, so if you plan on using for more than 60-days, you'll need to register. - Not easy to get account deleted.
>> Bitdefender offers no additional third-party software. Anonymous data collection is On by default.
Avira Free Antivirus utilises Windows Firewall, so it may display Firewall as OFF, if you use Outpost as your primary.
>> Avira may offer Dropbox software.
>> Avira Launcher will be standard in the setup, can be uninstalled post-install.
http://malwaretips.com/threads/avira-launcher.31440/