I've never tried it at the Sheraton or any other hotel in CDG, but lot's of airport hotels offer reduced rates for 8-12 hour stays as "day rooms."

Might want to see if you can land, get a room and nap for 4 hours, then leave you bags with the concierge and go see the city refreshed.

I have had them keep my bags for me even when I wasn't staying, but I've stayed there several times, so maybe it's because I was a known guest.

Thinking about it, I'd be very interested to know if they do let you do that at the Sheraton. Please let us know if you get it.