the tu-22m3 is just another russian "cool toy". it indeed has superb performance, and can pose a threat to any cvbg or neighboir nations. but i think it would be much wiser for the plaaf to custom order its tu-22, if it intends to aquire them. the "off the shelf" tu-22m3s are from the russian air force, and are at least 15-20 years old. besides, the plaaf will likely use these assets for a somewhat different purpose than russia. in russia, the m3 was an anti cvbg naval bombaer. in the plaaf, it will serve as a multirole strategic bomber, and thus needs upgrades to fill that role. some upgrades:
a new fire control radar to guide Chinese cruise missles and stand off weapons, and other tv or laser guided bombs. this might be the main issue, as russia only lets china use russian missles on the su-30s and j-11s.
stealth. not full stealth, but a similar to b-1 upgrade. ram and some polymer components can really lower the huge bombers rcs.
some 21st ceturey avionics and ecm. the advanced electronics will greatly increse the survivability of the plane over hostile territory. as russia has shown itself capable of making these advanced avionics, thw plaaf should settle for nothing less than the best.
and the backfire needs to cost around 80-90 million a peice to be reasonable. i wouldnt advise on aquring more than 2 dozen.