On an evaluation version of Windows 7 (Home Basic 32bit) on my notebook, Windows Defender is working OK. Instead of using MSE, as I normally do, Time Warner gave me a free security suite, CA Internet Security. It installed really easily, even the firewall, everything was automatic. It's the first time ever that I haven't used the Windows Firewall. It's also the first time that a firewall had the intelligence to install itself, w/o my input.
So far, so good. I'm able to use Defender, it updates and runs at 2AM. I haven't used it since my XP days, so I'm now getting to know it better. It's certainly a good app to have in your toolbox.
As for CA Internet Security Suite, it's done well so far. I'm scanning behind it with Malwarebytes & Windows Defender, no problems as of yet.
Cat