This is how it goes:
Series 1 Great (9/10) Series 2 (BIG change of cast) Not so great but I got used to the new cast members (7/10) Series 3 and 4 ... Like series 2 - some funny episodes but I still miss actors from series 1 (7/10, 7/10) Series 5 (Another big change of a cast member) Just really never worked for me.(5/10)
Series 1 Great (9/10) Series 2 (BIG change of cast) Not so great but I got used to the new cast members (7/10) Series 3 and 4 ... Like series 2 - some funny episodes but I still miss actors from series 1 (7/10, 7/10) Series 5 (Another big change of a cast member) Just really never worked for me.(5/10)