For me they are both great and as always you have to try them both to judge! Bitdefender has great protection but its extremely heavy on system resources and ESET has great protection as well and its super lightweight on system resources. So for me ESET would be ideal!
Without a doubt, I choose ESET Smart Security 7, Bitdefender is still too much heavy to be used dailyly on some computers, unlike ESET, which may be less powerful, but so much more lightweight! ^^
Frankly, BD doesn't have a higher detection. They both more or less cover the same but to me Eset has always been stable and i can't say the same for BD. No contest whatsoever here as far as im concerned.