Well, isn't flex watt a bit more difficult to set up? I thought flex watt was the choice if you were doing a rack system, and an UTH would be easier to set up for just a single tub/tank. Also, if I use an UTH that doesn't get terribly hot anyways, and I have a probe to double check that temperature, shouldn't I be fine? A herpstat might be a good investment though, it would run me $70 more, right? (~$100 for the basic model, iirc)