Ahhh the backup power question...
First, and as a note to other posters here, there is usually a significant difference between nameplate power consumption and actual power consumption. If you figure your wattage by adding up nameplate values, you will likely end up with a much higher value than you need. Most equipment draws much less power than the nameplate suggests.
My advice would be to spend $25 on a kill-o-watt. Plug all of the equipment on your tank that you plan to run with the generator into a power strip, plug the power strip into the kill-o-watt, and read your watt consumption. You may want to take several readings over the course of a few days, and go with the biggest reading.
Then do the same with anything else you want to run. Add everything up, then add about 20% for overhead, then get a generator that can handle that wattage continuously. Manufacturers often exaggerate their machine's capabilities by showcasing the surge power output rather than continuous, so beware of that. If you go with surge rating you will overstress the generator windings and you won't have surge capacity available to start things like refrigerator compressors.
If you are plagued by numerous outages, need a very quiet generator, or plan to use it for other things like camping, construction, etc, then a quality machine is what you want.
However if you are only concerned about emergency situations, then buy an inexpensive machine. The poor quality of the import generators will not be a problem if they only see rare and short-term use. Remember that with buying a portable generator comes the hassle of dealing with gas getting stale and waterlogged, so be sure to read on on proper procedures for long term engine storage.
Alternatively, you could purchase a power inverter. Here, quality matters, and buying something good from Tripp-Lite, Xantrex, APC, etc will be a wise investment. In most cases, an inverter hooked up to your car battery with heavy cable clamps and letting the engine on your car idle (not in the garage of course!!!!!) will get you through most outages. The plus side is that you won't have to worry about storing the generator, and dealing with gas going stale.