Yes, we too were looking into a backup generator for our home. We were interested in one that hooked into the natural gas to our home. So there wouldn't be any gasoline issues or outdoor generators getting stolen.
Run the costs on running a Natural Gas unit, I've heard it can be pricy. You mention outdoor unit getting stolen, were you thinking of mounting it inside and piping it outdoors? I always thought something like an gasoline RV unit w/ electric start converted to natural gas (there will be a output reduction doing this) could be tucked away well in a house (garage vented outdoors, maybe crawlspace cubby) and provide enough to run the fridge, a laptop and a router. Might not be so loud either. Neat stuff, if I had my own place I'd probably try to pick up a 30kw diesel with a double walled basetank. Almost bought one years ago for my wanna-be web hosting company in VaBeach, I think I almost had one for $2500 or so with 160 hours on it. They're out there.