Whilst peoples subjective opinions "I feel that" "in my experience" etc... are very interesting I thought I'd include this somewhat outdated survey:
http://www.iss.co.za/Pubs/ASR/9No4/Schonteich.html
It indicates that Tanzania does indeed have a low per capita crime rate. However it also indicates that where crimes do occur, the proportion carried out with a weapon are higher than average and actually higher than South africa. i didn't spend that long looking at the survey so please browse it yourself.
Bear in mind too that statisical evidence gathering is also less reliable than in more developed countries.
I've also spent several years on this continent and I'm sorry Mukosha but many visitors do experience a "honeymoon period". I've travelled here extensively using local transport, hitching and eating at roadside restaurants. Whilst I've usually had an interesting and pleasant time it is none the less a place where the onus for personal security is on you and not the state. In fact, the most threatened I've fealt here has usually been due to the police or military. That is a major diference between Africa and Europe or in fact East Asia.
Personal experiences will always differ due to length of stay, race and gender to name but a few, since we all experience different risks for different reasons.
It can be a great place to live, if you're relatively affluent but, I wouldn't like to be an uneducated local here!