I did not know that this series even existed until I was loaned it. To be frank, I am not a David Jason fan. I feel he is very overrated, however, I was quite impressed.
The pilot episode was not all that great. It was somewhat predictable and reminded me of that wonderful film "Two Way Stretch". The plot, without going into detail, being the same, only much better. However, as the series progresses it improves considerably.
It has a wonderful cast and although the scripts have been slated on the internet, I disagree. There were some very clever ideas.
My only criticism is that David Jason was a little long in the tooth for the part and in spite of his oftimes excellent disguises, still sounds like Del.
Overall, I would certainly watch it again.