The truth is it's a very good product, in my opinion. It's earned Advanced+ and few false positives according to AV-Comparitives, it's fully certified, and of course: it's free. It's about 7 megabites, which is decent for a traditional AV. It has Microsoft's built-in SpyNet which serves as sort of a "cloud-like" submission system. It's super simple, like Prevx is, even a notch more basic being without heuristic/self-protection controls. It takes up a fair amount of memory, which could be improved on a bit. It has very good detection ratings and is considerably, exceptionally advanced while remaining so easy to use. I am a true fan of Microsoft Security Essentials. No more *cough* AVG Free *cough*... If you want a free anti-malware solution, you go with Microsoft. The only advice I have is if you are using it solely, make sure you use a LUA/SUA for Internet activity, because I'm not yet certain how strong it's self protection is. I know it is protected by UAC and that makes it tamper resistant, but I'm not sure how hackers might exploit it. My cousin refuses to use it because he feels being free and by Microsoft it will quickly become the most exploited, but my response to that is: Norton and McAfee, the two big baddies are going to have to figure out how to stay alive and fast, and they still are going to be the ones pre-loaded on new PCs. So don't worry, plenty of PC newbies will still have the big baddies pre-loaded. Use Microsoft Security Essentials alongside Prevx for ultimate, reinforced second-opinion security.