Yeah it's tricky. I've generally had a good experience with IDNet but they have their poor moments. I remember the first time I was with them when it was mostly my persistence that got Simon to track down a misconfigured LNS that was causing single threaded speeds to be throttled to 10Mb/s.
And I left Plusnet to come back because I was fed up with having to fight to get Support to take issues seriously (plus it was embarrassing telling my technical friends that I still didn't have native IPv6). But I don't want to pay any more and I do believe that IDNet care about their service I just think we have to get through first line support.
But it's close to the point where the only thing holding me back from a change is lack of choice and the hassle of reconfiguring my domain.