Congrat's on your new purchase.
As most have said it is a personal preference but I always get the toppers. I for one believe in staying off the roof as much as possible.
We use our Honda 2000i with our Cougar 327 RES and have no problem running the outlets, just remember that you have a limited amount of power supply i.e. when on the Honda we run the fridge on propane, don't try operating multiple small appliances like toaster, coffee maker and hair dryer all at once as each will likely draw about 1500 each and you are limited to 2000.
Overloading the 2000i will cause it to cut off power.
2000i is very portable, good on fuel and whisper quiet.
3000i is another option, bulkier to maneuver but will run more appliance.
GPG