I currently have two Internet Service Providers (ISPs): M-Net and PŸUR (previously known as Cablesurf).

I have been a customer of M-Net for about two years, and am generally pleased with their service.

I have been a customer of PŸUR much longer (about 17 years). Whilst they are cheap (the cheapest ISP around), I have always had trouble with their service:

• They have never offered the option of static IP addresses, which is problematic when hosting web-sites; in the early days the IP address changed very infrequently (once every few years), but more recently my IP address has changed every few months;
• The upload speed (the most important bandwidth figure when hosting web-sites) has always been very much lower than than the download speed, with no option to get a higher proportion of the bandwidth for upload;
• Just recently, whilst checking my PŸUR addresses (IPv4 & IPv6) in case they had changed, I noticed that the new IPv4 address started with "100." which is in a range reserved for NAT (Network Address Translation) connections (like the "192.168." address that your home LAN probably uses): what this means is that my PŸUR Internet modem no longer connects directly to the Internet, but instead connects to their NAT router, meaning that I can make outgoing connections, but no-one can establish an incoming connection, which is useless for any web-site that I host; my PŸUR IPv6 addresses are of course still reachable by Internet users, but much of the world still doesn't have IPv6 connectivity (see the map to the right).

It is not unusual for ISPs to change their Terms and Conditions, but, in Germany at least, all service providers (not just ISPs) are legally obliged (obligated, to US readers) to inform their customers. Changing Ts&Cs without due notice is a breach of contract. If I had time, I would sue; I will definitely cancel the contract with PŸUR, since I can operate my web-sites effectively with just my M-Net service.