40 for 50 is not so bad. Some regional ISPs installing FTTB/FTTH offer 100mbps + voice for ~40€, which is a pretty good deal.
Due to heavy oversubscribing cable is an inferior product in Germany (on weekends actual speeds drop to a fraction of the advertised line speed), and the biggest cable provider by far (Kabel Deutschland/Vodafone) has serious user support and service quality issues, not to mention they only offer ipv6 dual-stack lite connectivity.