I've got a Challenge Steam generator iron, and just an ordinary steam iron. The generator iron gets used the most. It seems to have far more steam power, and irons both sides of the garment at once. It "blasts" the steam right through. I think it's really good!!!
i bought one similar to this, a morphy richards one, but it was reduced from £120 to £35 or something ... it is excellent, i am really pleased with it. it is noisier than a regular iron but is better at getting creases out and it is quicker too.
I bought a Domotec one, but it broke after a few months and I haven't bothered replacing it. Okay, they get the creases out well, but they can be diff. to manoeuvre, with the heavy base unit etc, which really needs to be on a kitchen surface/unit, rather than ironing board, as it makes it unsteady, then there's not much cord left etc etc. Bit of a faff, I thought. I'm sticking with my regular steam one.