Just cause it didn't notify you doesn't mean the definition file had it flagged meaning you might have had it but didn't know it cause it wasn't detected I use avira free and malwarebytes and once in a while it finds something. But never had problems with comp so far
it's definitely the best antivirus when you sum all the properties; speed, db, performance and the available cracked versions
I used NOD32 for a while when I first got Windows 7, loved the way it felt so light on the system & scans were fast too but then started using MSE & I got into using Comodo Firewall as well so didn't feel the need to keep using it. Never got a warning when using it though, hopefully nothing got in.
MSE cannot even compete with NOD32 man it misses alot of viruses. You would never know obviously since you missed them. I've used it on my sister's computer only to discover a week later that her PC is fully of viruses when we scanned online.
That means nothing if you did not do full system scan when you installed MSE viruses may have already been present.
MSE hasn't let me down yet, I've been using it fully since it came out of beta & it's probably due to my browsing habits but I have never had MSE throw anything up about malware, it continues to get very good results from AV tests & has very very low FP's if any really. I use it in a combo though of Malwarebytes (On-Demand Scanner Only) & Comodo Firewall (With High Settings).