Country of manufacturing is not critical. It's the combination of design, materials, and manufacturing specifications that matter. As a sailmaker, I use the best Dacron available for offshore sails, which many in the industry would agree is something like Marblehead from Challenge. Depending on weight, it's usually somewhere in the $16-19 per yard price range. I could buy a lesser Dacron like the high modulus for $10 or $12 per yard. I could buy seconds or other factory reject cloth for as little as 20-30% of regular price. It's well known that some lofts will use seconds to achieve a low price.

Manufacturing specifications vary. The size and design of patches is important. The basic broadseaming of course matters as well. Is the stitching zig-zag, or the much stronger triple step? What about the thread itself? Did you know some of the better sails are now using Tenara thread reduce or eliminate the threads degrading from UV exposure?

In-mast furling sails pose challenges as we have to engineer a lot of strength into the sail without making it bulky. Radial patches are a must. Webbing straps on in-mast furling sails must be well done. I prefer to use Spectra webbing knowing that if a webbing strap fails at the head of a sail at an inopportune moment, the only recourse is to lower the sail and repair it. Spectra is stronger and lasts longer. Yes it costs a few dollars extra.

I think many sailors assume all sails are more or less equal. That is generally not the case. It's a competitive industry and we don't see substantial differences in pricing for comparably manufactured sails. The margins simply aren't there. There are usually some major differences when there's a large disparity in price.

My advice is to ask a lot of questions about material and construction.