Fireman Sam is a two-sided affair. On the one hand, because the first 4 seasons are a long way from the later ones, but above all because the switch from stop-motion to CGI animations has given the series an extreme kink. In addition, the stories are designed to be more superficial and less value-oriented. So you can rate the first seasons with a very good 9 stars, the later with a lucky 3 stars, so that in the end (unfortunately) an overall rating of 6 points comes out; and that's still benevolent, because the CGI era is much more extensive than that of classic stop motion.