I have been using BD for many years, I recently installed 2011 IS on my system to test before I install it on my customers PC's...
1) The PC sits idle for most of the day, I do this at different times, I get home and go to use my system BD decides to do a system scan (which takes up 100% of the process) and at the same time it decides to do a update, even though I have my settings set to do it once every 12 hours... This is not a quick scan it is more like a full scan, it takes about 1-2 hours to complete.......
2) I did my first "deep system scan" which I scheduled to start at 1:00 am every 3 days as I always have done in the past versions. I get up this morning and BD is still doing the scan and has 60 hours to go to finish???
I use Win XP pro with all of the patches.... I have to say I am disappointed in BD last few versions, 2010 constantly crashes, disables the realtime protection and corrupted a 16bit database application while doing a scan & which I had to rebuild....