I have tried more than a few antivirus programs before I settled on Dr.Web. Some of the qualities that I like about Dr.Web are;daily updates,light resource usage,a mail scanner(Spider Mail)that works well.Spider Guard is the monitor component.Mousing over the spider icon gives current data like files scanned etc.. Dr.Web is configurable so I set it up the way that I wanted.The scanner can use heuristics,scan memory,scan boot files,scan packed executable and archives.It scans fairly fast and is stable. The only thing to keep in mind with the heuristics is the occasional "false positive" which is usually identified as "probable infection.." I really like this program and I plan on renewing the license after it expires.