I was fortunate enough to obtain a Dartzeel CTH-8550 integrated amp recently. I am not claiming it is the best integrated period as have not heard every integrated created in history. I doubt anyone has.
But it is so good as to give my CJ ACT2.2 and CJ Premier 350SA a run for its money and is threatening to replace it. The CJ combo is up there with the best pre and power out there at its price point so to have an integrated amp in the Dartzeel provide a very similar level of enjoyment says it all.