Kaspersky is super accurate and doesn't bog down computer
Small footprint - doesn't hog resources, catches suspicious activity.
Download servers could be faster for updates.
The Bottom Line:
I feel that Kaspersky wins hands down over Norton and McAffee - friendly interface and very accurate at catching problems.
I have been around and worked with computers since the early 1980s. I am the neighborhood "geek" to whom everyone comes with their computer problems. Over the years, I have found two really horrible mistakes that people make with their computers which can seriously compromise security: 1)No buy a NEW antivirus EVERY year (not just renew the license) and 2) fail to have a good spyware program and perform weeekly scans.
Over the years, my reccomendations have changed as far as antivirus programs. In its infancy, Norton had about the best product on the market. As computers became faster and the Internet began to blossom with all types of applications, I started to recommend McAffee over Norton because the latter seemed to catch more of the yet unpublished virii before they became a problem. It used heuristics to look for suspicious activity. But as time marched on, McAffee and Norton began to become enormous memory and resource hogs. I would help friends and clients set up their new PCs that had either of these two programs pre-installed and they were absolute dogs right out of the box.
Then, I read an article in PC World magazine and CNET reviewing Kaspersky Antivirus. They praised its ability to catch more problems than the other two contenders AND it had a relatively small footprint. It has been 4 years now, and I am extremely pleased with the performance of Kaspersky. I especially like the fact that I can buy a license for 3 PCs which is great because I have multiple computers in my home. Kaspersky has also developed a scaled-down version for the new tablet devices on the market (Sorry - no Apple, only for Androids). I am especially stressing the fact to friends and neighbors that antivirus is going to have to become a standard for all smartphones and tablets because more people are going online with these devices for online banking, shopping, etc., and if they happen to open an infected attachment in their email, we can start seeing havoc being wreaked on these new devices.
The most important thing to remember, if you purchase Kaspersky, is to completely uninstall your previous antivirus FIRST. Then install Kaspersky. After a reboot, Windows will remind you that the antivirus database is out of date and you will be prompted to update. Kaspersky's servers aren't the fastest that I've seen - updates in the beginning (because they are large files) are painfully slow, although this doesn't affect performance of other programs you may be using at the same time.
By default, it has a schedule to check the computer once per week. I recommend that you choose a day (if you don't leave your PC on 24/7) and a time in the middle of the night to perform a full virus scan.
Kaspersky's heuristics are amazing - they have caught problems that haven't even been documented. The designers have done an excellent job in creating this product. Just remember my recommendation (no, I'm not a salesman for them) is to buy a NEW version EVERY year. The reason is that the companies that make antivirus programs always improve the accuracy of their products for the next year's version.
In conclusion, I would highly recommend Kaspersky Antivirus. It doesn't hog resources and bog down your computer and is excellent at catching suspicious activity.