I have been using Blacknight for domains and hosting for years and find their service is excellent. Last year, I got their fibre broadband after Eir gave me the run around for 5 months. In less than a week, I was up and running. I have the 500Mbs fibre to home and constantly get the advertised speed. Even watching a 4K movie, the drop is minimal.
I cannot fault the service that Blacknight have given me over the years. They are the benchmark for other Irish companies