There has been a lot of discussion about this topic on here, so u could try a search for more info, i know this as i have just yesty done this very thing based on most of the feedback from this site, which was very informative.
I went for the Honda 2,0I, or 2KVA gennie, i to thought of only the 1KVA, but would rather a bit to much then not enough. The Honda for me was very close to the Yamaha, but as i have a few Honda products, which include a dirt bike, lawn mower, blower and a couple of others, and have never had any trouble with them, the choice was pretty easy.
That said, i think the Yamaha would also be a very good unit. Honda at present have a very good deal going, $300 cash back and a few extras to go with it, i bought mine from Aquip field days yesty for a great price, $1600 which was field day spec.
If you Google Honda generator u will find the sites that are offering the deals i spoke of, u cant go wrong.
I have no affiliation with Honda wat so ever, i'm just a very happy owner of a number of products, my prized possesion would be my XR 650R which rocks the house.
Good luck enjoy the search.
Swanny