I've seen several with good ratings...Should I get one?
I wouldn't bother.
It's going to tie up resources on your device and provide no real protection. Anti-virus doesn't help much with Malware... Most issues 1. Are out of China 2. ALL involve permissions granted to apps.
Be safe and always download/install from a reputable source (ie MarketPlace) and pay attention to what requests for permission an app is requiring. You have to confirm and OK them so you always have the option to check.
...but seriously, I'm just kidding.
There was a sticky on here a while back that talks about task killers and anti-spyware apps and why they aren't needed. Give it a look if its still up.
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