If you remember this from on screen in the 70's you know what to expect. It is based on the difficult time in the early to mid 70's when White British people struggled in their acceptance to the mass immigration of the Black community. They live next door to each other, the women get on and the men don't. The men also work together the White male character is portrayed as being quite working class and lesser educated, and continually calls his counterpart a "nig nog" and Sambo. Whilst the Black Male character is scripted as being more refined and well read; he is also very capable of racism though; he refers to his opposite as a "honky" or "snowflake".
Whilst being very popular during the early to mid 70's it did make rise to a great deal of criticism due to it's complete disregard to social cohesion and acceptance, if you were to study the episodes you do see racism on both parts. This boxset includes all 7 series which ran from 1972-1976, it did create similar controversy as did "till death do us part" due to the (in some cases) harsh racist comments and actions.
This will be something you either love and find hillarious or you hate and would find offensive. If it was to be aired on television these days it would have a continuity announcement warning of the likelihood to offence that may be caused.
I would recommend that you ask someone who knows you well and that remembers it as to whether you would enjoy this.