From working with with hundreds of Bitdefender installs I have felt and experience what it does first hand on many different levels. From schools to personal computers .. Ive had to trouble shoot it. Every single one of the guys I worked with in the industry knows the crud it can cause or the errors that pop up around it. Its honestly terrible.
Why is it so popular? Simply put.. its where sales and technical dont come together. We hated our sales people for selling BitDefender as we knew the kind of support we had to do afterwards. Sales sold it because out of all the AV`s out there.. it has the highest markups for them. Thats why its pushed so strongly on the market.
I know it works for some people just like some people will swear by Nortons... but I wouldnt install it on my system.
Ok, fine. I haven't had issues with BD myself, it runs fast on my C2D ULV 1.6GHz machine and ran fast on my Pentium M 2.0 as well. I've had Kaspersky mess up MS Office 2007 though at a friend's place and I've had Spybot make FireFox update issues but other than that BitDefender has picked up viruses on USB sticks and occasionally on websites. BD is also pretty cheap, it cost R200 odd for a 3 user home license.
Are your issues more with support for multiple user/network environments or more with missed viruses?