I have run it up and dwn and still ramps really fast and the temp up and dwn. The tc coil is nickle. If tht helps. I got two packs of the tc coil bc of price but then got into wattage and like it just as much if not more. Trying to get some use out of these coils some how. Unless I just use for my higher nic juices 3 to 6 nic. I am usually 1.5 nic on my rda and other tank that I occasionally use. Thanks @greasegizzardWhat do you have your watts set at in TC mode? That will affect how fast it ramps up.