BD and Comodo are in the same boat together... although I can get CIS to work very well on my W8.1 system, that just isn't the case with BD. That's my experience with these products. I'm sure someone out there can say the exact opposite.
I have used Bitdefender for some time and found very few bugs, yeah there have been some but all AVs suffer from them. As to Comodo, I wouldn't touch it with a bargepole - even if someone else was holding it, but we are all different, have different set-ups and prefer different things. If we didn't everyone would be using the same AVs, Os's, programs.
I understand it, I had some problems with Comodo too (including some bluescreens) but BD (for me) is even worst. Some years ago I had found dozens of bugs (nothing serious) but, for example, I can't use the latest version because it increases my boot time a lot (from 2/3 seconds to 1 minute).
For me ESET is the best in terms of performance/bugs (Thank you @exterminator20).
I will try the new BD 2016 but I don't expect anything good, let's see if I'm wrong
They acknowledged the boot time was a problem and now have a setting to turn it off, Windows 7 is back to its normal 20 or so seconds, win 8/8.1 is as instantaneous as it should be.
I understand your reluctance to use something that gave problems, I do the same.