Norton System Works Premiere preformed very well during my testing period. I must admit I was a little weary of trying Norton again because in the past I have had trouble with the anti virus significantly slowing my system. An when I installed it, I experienced a very long boot time, and was afraid this program was much of the same if not worse. Fortunately the boot time issue was a one time thing, and now my system works very efficiently. I preformed some benchmarks before and after installing the system, and after running the system optimization tools. there was no loss of speed in most tests before and after the installation, and those that we lower were still very close to original benchmarks. After running the system optimization tools I noticed a boost in boot speed and application launch speed. The benchmarks showed some improvement in most areas, although it was not significant. The tools worked flawlessly, yet the interface could use some improvement. Over all I was pleasantly surprised with the improvement in antivirus performance, and the tools worked well. The price tag is somewhat steep but if you watch for rebates you may even find help in this department. For those of us dismayed by the poor perfomance of System Mechanic 7 this is a good alternative.