Rottielover,
As you can see by my tag line I am directly involved in this arena. Your treatment by Horizon, with the possible exception of the time delay was more than fair. When it comes to warranty customers seem to think it's always easy and black and white, not so, the things some try to get away with are astonishing and some times comical, and I'm sure Shawn Evans from Yellow will back me up on this. Just to give you a small example, we had a customer demand the replacement of a plane / engine combo because the instructions did not give step by step procedure on mounting the battery and it came loose in flight, another yelled at me for 20 minutes because we didn't tell him in advance he needed to reverse an elevator servo so he thought I should be responsible for the purchase price of the component.
Now nobody is saying your description of the events isn't 100% accurate, but from this side of the fence after a while it gets tough to tell.