A fighter aircraft's marketability is based on the product design, capability and what the final product will be. If Shenyang displayed its FC-31 on the European market, it is most likely to get PR points. The aircraft has received a lot of notice, globally. It is only a matter of time, a serious buyer will emerge for this aircraft. Like any product, there must be a baseline version which meets the standards of the product type, it's capabilities in comparison to other similar products on the market. On such a premise it is safe to assume that there will be further development on the FC-31s. Politics aside, the interested buyer would buy regardless of the political implications. So long as the manufacturer has a finished product. There isn't any doubt whether if FC-31 would take to the skies, with some country's ait force. It's more a question when. Time will reveal the truth, one just needs to be patient.