The only real problem I had with using it back in the day was when I had to incorporate octal into programs. That system made no bloody sense whatsoever.
I had to embed hex into COBOL programs to send data to a laser printer - Canon told me I was the first in the UK to do it. Unfortunately no one else in my team could get their heads around it and so all future wierd and wonderful stuff got dropped on me, like outputting to Oracle database, Word and Excel, nearly always wanted yesterday.
Did octal, binary etc at school. We were the first year to do what was then called "Modern Maths", Boolean algebra and stuff. Unfortunately they introduced it at the beginning of the first term of 4th year, so we had to forget 3 years of trad maths and only had 2 years before taking O levels. That was fun, many people could not hack it at all.