Brittany man, Have you experienced any burnishing of the bluing on the ends of your barrels yet? I found that it is impossible to clean out sleeve style cases, and the constant sheathing, unsheathing wears away the finish on barrels. And, I could never dry one out. I have a bunch.
I am in the field most everyday, and whatever firearm I am using gets cased/uncased a dozen or more times per day. I will admit that other than a rag with rem oil my shotguns basically get a rag-off, then into the case.
A damp case will etch whatever weave the lining exhibits into any blued surface very quick. I have a GR6 Browning Citori with some sort of damask pattern etched into the barrels from sitting in a case that a cooler dampened.
My choices and behaviors certainly don't mimic those of others, and unfortunately, I have experienced about every way that a firearm can be damaged.
The big difference between $1,000.00 leather cases and $250.00 cases is whether they are made with 1 hide, or 3 pieces. Oh, and whether or not the maker attaches an embossed label. Also, if a person travels, and wishes to carry matching accoutrements, not every seller has a full leathergoods line to attend the cases.
Having handled 6 or 7 brands, it was obvious that only a couple companies in the US make all the private labled sleaves.
On any of my excursions, the most glorious moment is when I unsheath my sabre of the day.