Unknown manufacturer.
Unknown design.
Unknown reliability.
Unknown accuracy.
Unknown build quality.
Unknown warranty service.
Unknown parts compatibility.
Unknown parts availability.
Unknown price, but suspected to be $1400.
vz58, M17s, XCR, ACR, Tavor, M14, Mini 14, Type 97 and any other gun currently on the market is better than the Jard J48 because all of these questions have been answered. While some of these guns vary in each of the answers to these questions, the answers are known as either good, or bad.
Until this gun has more information posted about it, that can be authenticated, it is an UNTESTED and UNPROVEN design. Not a BAD or POOR design, or a good or excellent design.
Because the questions have been asked, and no answers are known.
Until then, $1400 is a tough price to swallow for a gun that no one public knows anything about.