When my cheap soldering iron died I decided to use its case to build a temperature controlled hot plate so I can reflow surface mount pcbs. I used the Rex-c100 along with a solid state relay and 2x 300 watt cartridge heaters. It takes it a couple of min to warm up but it works quite well once its to temp.
I completed the controller. It works quite well. The aluminum plate has quite a bit of thermal mass so it retains heat for a long time. If there is interist I might post a video of me using this to do some smt soldering. It sure beats using a regular hot plate.