Bests & Worsts Reviews from Amazon

I purchased this heater with high expectations as Eheim is (was?) one of the higher quality manufacturers of aquarium supplies. However, I must now say I will not purchase another Eheim product as the heater was defective and, while manufacturing defects do happen, the attitude I received from tech support was the final straw. This heater allows for recalibration if the temperature of the water in the tank does not match the temperature at which the heater is set. After having the heater in the tank 24 hours, the water temperature was much higher than the setting so I followed the directions for recalibration. After several days of adjustments, the recalibration ring was set as far as it would go, the temperature ring was set at 75 degrees and, the unanimous reading of the 3 different types of thermometers was still 79.8. While I can continue to set the temperature lower to reach the desired 78 degrees, the accuracy of this heater should not be that far off and I question its reliability. One nice thing about this heater is, as far as precision is concerned, when it settles on a temperature (right or wrong) it does hold to the tenth of a degree. I recently emailed Eheim expressing my concerns regarding the lack of accuracy and requested a replacement heater considering I was only a couple months into a 3-year warranty. The response I received was to restore the heater to factory settings for 24 hours then let them know what the temperature was. Since the temperature was already running higher than set, returning the heater to factory settings would put the water temperature in the high 80s - low 90s. Not wanting to kill my fish (including a 14-year old clown loach and 3 near hand-sized angel fish), I called tech support this morning and got absolutely no where. As per the rep, they won't honor their warranty if I don't reset the heater to factory settings and verify the temperature yet they aren't about to replace my fish. As I do not have a back up heater, testing the Eheim in a bucket is not an option, neither is returning it to them for verification. The rep I spoke with was rude, unapologetic and refused to let me speak to a supervisor as he said I had no reason. Fortunately, Amazon came through and offered to refund my money. Between the lack of accuracy of the heater and, even more so, the complete lack of customer service, the new heater will NOT be an Eheim!