Generator question - worth it to sell Champion gen for Honda

I've used both in business and the Honda is quieter to my ear. If you haven't listened to a Honda 3000, maybe a dealer will have a demo you can try. Bring your Champion and test them side-by-side. A smart phone app that has a sound meter could compare their output sound levels against each other.
The specs state that the Honda is also 20 pounds lighter.

I think the weight difference is a bigger issue than the sound issue personally.