Another vote for the Honda. I've had one for over 10 years and it still runs like new. I change the oil every other year or so and use the best gasoline, and that's it. They're cheap (relatively), portable, bone solid reliable and really, really quiet... Oh, my version also has 12 volt output pins.
Of course, given you know you want to continue to use Quadras, and given the cost of a good portable gasoline generator, it might make more sense to simply pack extra charged Quadra batteries -- unless that is, you plan to be outdoors for extended periods of time...