MSE has been tested thoroughly, by several of the accepted testing bodies. Personal experience isn't worth much, but I'll tell you that it and Avira are the only AV products I've seen warn and prevent the Facebook virus from infecting a system, of the ones I've seen.
My Computer
At a glance
Windows 7 Ultimate x64 SP1Intel Core i7-260012 GB Patriot Extreme DDR3-1333Nvidia GTX 470
- OS
- Windows 7 Ultimate x64 SP1
- CPU
- Intel Core i7-2600
- Motherboard
- Gigabyte GA-P67A-UD3P-B3
- Memory
- 12 GB Patriot Extreme DDR3-1333
- Graphics Card(s)
- Nvidia GTX 470
- Monitor(s) Displays
- Dell UltraSharp 2209WA
- Hard Drives
- OCZ Agility3 240 GB, WD5001AALS, WD7501AALS
- PSU
- OCZ ModStream 700W
- Case
- CoolerMaster HAF 912 Advanced
- Cooling
- CoolerMaster Hyper 212 Plus
A very nice feature which helps page load faster.