I switched to IDNet circa 2006, when I had had problems with previous ISP. One of our network engineers was having similar trouble and I piggy-backed on his research to move to IDNet. It's reliable service, not cheap but definitely value for money. The best part about it is the customer service.
You get your call answered in a few rings, by a person who is allowed to use their brain and does. I'll give an example of the rare times when I've needed the service.
If there's a problem, working with them feels like troubleshooting with a colleague, not like the usual battle to get off the script and use some common sense.
Once I had a problem that required a BT engineer to go up a pole in my neighbour's garden. Said BT engineer tried to tell me the problem was my fault because of a bent cable in my house (really.) I knew that was BS but didn't have sufficient knowledge to refute him, so I rang up IDNet again. We ended up with the IDNet guy, who was a former BT engineer, telling the BT guy what to do and although he whined and moaned, he did it and the problem was solved. A few hours later the IDNet guy rang me to make sure everything was OK.
Try that with the ones that advertise that they are cheapest. Helpful hint: they are.
IDNet has customer service that ought to be the norm for everyone, but sadly is not.
Time With Provider: 15 Years
Package Name: Unlimited Broadband