Sorry, but right if You are open minded then there's absolutely no sense in buying is dying dinosaur. YES for sure, the Backfire is - or better to say was - one of the most impressive military aircraft ever build (IMO), but what would the PLAAF or PLANAF gain ... and even more at what cost ??
1. Impressive performance superior in some respect to H-6: PLUS
... but that can already be done with modern ASM/AGM/BM ... making it a nearly MINUS
2. dated design with high operating cost: MINUS
3. if possible at best a lumbering, rusting manufacturing line, which was out of work for decades: MINUS
4. YES, high performance engines (which are not quite modern ...) and were no longer in production since years: MINUS
4. completely new chain of maintenance and logistics: MINUS
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As such this deal would have been fine in the 1990s but not now as with a simply open minded calculation I think the NEGATIVE points are more than the POSITIVE ones.
Deino