A group of 3 campers that include myself, my dad, and a buddy spend at least 3 weekends a year camping together at various race tracks. 3 years ago my dad picked up a pair of the 2000 watt champions. I have 2 EU2000's.
After 2 years my dad bought a motorhome with an onboard gen and no longer needed the champs, and sold them to the other buddy who had been using a contractor genset just to charge batteries (when cars were on track....otherwise it was too obnoxious). my point is that I've spent a few weekends with direct comparison of the honda 2000's and the Champs.
In terms of noise - the Honda's are quieter by a bit. It's not a huge difference....if they werent in close proximity you'd never know.
One area where the champions seemed to struggle was with air conditioners. Even with hard start capacitors installed and other loads either removed or greatly reduced they seemed to cut out an awful lot when AC's were fired up and/or run for a long period of time. I've never had that problem with the Honda's on my 15k btu AC unit. I dont know if they were just bum units in that regard or what. In cooler weather without AC the champions performed otherwise admirably.
Just my experience.