Too good to be true??

I`m using free antivirus- active virus shield,free windows defender, free antispyware-spybot s&d and Adware se plus free spywareblaster. I havent had a major virus problem so far .But still something in the back fo mind keeps on telling me that this is could be too good to be true.Does anyone have the same feeling?How can i find out that there is nothing hidden behind these `free` security softwares.Maybe i`m just too paranoid….your views will be greatly appreciated.

2 bad 2 b false

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