Claremont
Cossy
Gingster
I don’t fancy taking it to the launderette every 2/3 weeks. We have king sizes
I have mine collected and returned 
Interesting - how much though? each time and per year?
I once had a king-size man-made duvet collected, washed and returned. £20 door-to-door. If I did it again I would use a different firm, When returned it was covered with tiny down filaments, so must have been washed in a huge machine along with feather/down duvets, and it smelled strongly of industrial detergent. I vacuumed off the down, and the smell eventually disappeared after a week or two draped over the landing banisters.
However, that was just one experience (I discovered that the "laundry" that did it was just a single bulk washing machine in a back room at an industrial complex) Someone "taking in washing" a a sideline.
I replaced that duvet with a smaller one that I could get into my own machine. Now no trouble washing it myself