So the salesperson couldnt explain the difference?
Also I think the spring down cushions will not be all down, but the same mixture of blend down. Typically a blend down fill is 50% polyester fiber and 50% of down and feathers. The ration of feathers to down can vary from about 75% feathers/25% down to 90% feathers/10% down.
Actually, the best deal will ALWAYS be to buy direct from the manufacturer.
If you search for "Factory direct custom sofas", just beware that some retailers will advertise they are factory direct. Usually that can mean 2 things, they are factory direct from China (imported) or they just claim to be factory direct, but actually they dont own a upholstery factory. As almost all retailers buy from a factory then resale to you. You need to find a actual factory that sells direct; no middleman.

Thank you rmanbike. I appreciate your input! I've read lots of your posts over the years. The cushions in both lines are the same I believe. They are spring down w/ a blend of fiber and feather/down. The feather/ down ratio is 75/25. I initially thought it might be a differenct down proportion- i.e. more down in the more expensive line. Since I like down but am perhaps unusual in that I prefer a fiber down blend ( because I think it keeps the back pillows in particular more shapely), that would not bother me. Since the cushions seem to be the same, I was just wondering if it is a construction issue. I'd ideally like a piece that could be reupholstered down the road.

It has been a decade since I researched sofas and the one I bought back then is as solid as a rock. Cushions are like new. I would re-upholster except I want a different number of cushions and a very different arm style. I also want a 'cleaner' look with more pitch to the back.

Now that I am back in the market for upholstery, I see that so much has changed. I came very close to ordering a Hickory Chair sofa- I like the style, the cushions, the arm styles and especially the fact that you can order in one inch increments. I need an unusual size. But given the uncertainty still looming with all those Furniture Brands Intl companies post bankruptcy, I am hesitant to order. My local dealer was very honest about the situation (I appreciate that!) and they are discouraging orders. That is how I ended up considering Hickory White. (& Century too.) HW does not offer a by the inch program so I am locked into length.

Thanks again.