I used to research heaters and look for the most trustworthy- I've seen brands rise and fall and to be honest, I haven't seen a single brand of heater that doesn't have a horror story. For me, I simply buy really cheap heaters that aren't prone to explode and hook them up with a controller to monitor them in case they get stuck on or to monitor their wattage in case they fail (and I always run two smaller heaters where one heater couldn't cook the tank if the controller failed). I check them every 2 months and donate every year like clockwork. I'm a believer that it's not a matter of if a heater will fail, but when. Most of my heater failures were around the two-four year range, so I find replacing regularly seems to reduce my chances of failure and I haven't seen a rise in the failure rate of the cheap heaters within the first year.