If you get a dual fuel make sure the power rating is sufficient for the fuel you intend to use. For Propane, the rated power is generally about 10% +/- less than with gasoline. May not make a difference for you but be sure you consider which fuel you plan on using.
If this is true, that the power output could be less, definitely look at what you're hoping to power from the generator if you'll do a propane conversion. To run my A/C unit I don't think I could run it on 10% less power from my Honda EU2200i.
I seriously considered a propane conversion, but I decided against it for two reasons:
1. It will take a lot of propane to run the generator for a long period - say, overnite if you're using it for A/C, or charging batteries for hours. You won't have enough propane on board to support that for more than a day or two, most likely.
2. When you run out of propane you'll have a VERY tough time finding a marina that can refill the propane cannister. If you use gasoline, almost any marina can refill that fuel source right at the dock.