i've used those Antex Irons... i found them INCREDIBLY annoying to use, both slow to heat up, got too hot (no temperature control) and the heat is distributed all over the front end meaning that half the iron is radiating hot air, leading to burns if you have to hold it at an odd angle.
not to mention, the three-inch-thick mains cable got in the way all the time.
Also, with an iron that's too low a wattage, you've got two problems, Firstly, it takes too long to heat the subject material, meaning you have to hold the iron on the component for extended amounts of time, possibly leading to component damage (and melted wiring insulation!), and Secondly, if you're soldering something with a large thermal capacity, the iron will cool down and take a long time to get back to temperature, this also applies when you're cleaning the end of the iron.