I have one of these (although badged slightly differently). It's fine for a while, but don't rely on it long term. The metal is very cheap and as soon as it's out in the rain, it begins to rust. While this is not a problem for the frame etc, it's a complete PITA in the fuel tank as it fills up with rust meaning I have to drain the tank most times before using it and often clean the carb - a complete pain when we rock up in an MX paddock in the dark at this time of year and have to spend the first hour fighting with the genny while the kids keep asking if they can watch telly/DVD/playstation yet .....
It got to be such a pain I have just brought one of these:
It's very light (22kg), runs about 5 hours on a tankfull and produces a 1.8kw constant load (2kw max) digitaly corrected output. Very pleased with it and worth the extra money over the old one. PS - you can have my old one FOC if your in Kent and want to pick it up !!!