i was in the same situation as you (expired nav), and started using avg after getting recommendations from this forum ... i'd say it's good and it's working well
one experience that i had was i got alert from avg when it read a cookie that contains a "harmful script"
i never got such alert before from nav (it's not the first time i visited that website), so i'm quite convinced with avg ... plus it's free and quite up to date with the latest virus development
and yes, i didn't get paid to promote them
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