As one of the posters in the linked thread who was suffering single thread speed problems, IDNet moved me from Zen to BTw backhaul and instantly cured my problems. Single thread speeds always within 1-2 Mbps of my multithread speeds.
As BF said, no ISP is immune from having problems. To me it is a case of how it gets managed when the problems occur that sets the better ISPs apart.
30 day rolling contracts and the ability to get a month's discount if you pay for the year upfront make them a really good option if you're willing to spend a bit more than the budget ISPs.