Cavani over Costa for me. Costa is a couple of years younger but there's Lukaku looking to break in and at 27, Cavani still has few good years at the top. Depends on price though, if PSG let him leave for less than 50mil (assuming FFP problems are true) then Cavani definitely but between Cavani at 60-70mil and Costa at 35mil, it depends on if Jose can fit Cavani and other preferred targets within the budget