I am a Brit and unashamedly supportive of my country - I could therefore be considered biased in this debate. However, the French are some of the most aggressive and unscrupulous arms and technology salesmen on the planet. The will sell any weapons to absolute anyone at all, without any embarrassment whatsoever, as long as they have the money. They sold Exocet missiles to the Argentinians that took out British ships. We, incidentally, previously owned the Belgrano and their Aircraft Carrier, so we are not blameless either. Those with long memories may recall the Israelis carrying out 'The Raid on the Sun' (Operation Opera, also sometimes known as Operation Babylon) on 7 June 1981 when their very nice new F-16s took out the Iraqi's nearly-finished Osirak nuclear reactor near Baghdad. It should come as no surprise to anyone that the reactor was supplied by none other than the French. They never gave a second's thought to the wider ramification of a madman like Saddam Hussein having nuclear weapons - it is all about having money in the bank after all.
Move now to the present day where the French have seriously got the hump because their not-so-posh submarines have been usurped by better offerings fro the Brits and Americans. Again, followers of history will know that it was the Brits who were the last to sink a ship with a submarine when HMS Conqueror (UK-built nuclear submarine with conventional torpedos) sunk the Belgrano in the Falklands War. There are a lot of things the Brits could do better at - when it comes to submarines, we do seem to be doing quite well. Does anyone seriously think for a moment the French would have hesitated to have stuffed the Brits or Yanks if the tables had been turned. These are the same French who thought nothing of blowing up the Rainbow Warrior on 10 June 1985 in Auckland Harbour - New Zealand being a major ally of the French and the Australians incidentally. Therefore, at a technical level, the purchase of British and American submarines, instead of French one, makes total sense. Again, followers of history may be interested to know that of the 59 submarines used by the French navy in WW2, 3/4 of them were sunk - not exactly inspiring stuff.
So, to the question of whether the Chinese care about 8 Australian submarines. Of course, they are not running in fear of their navy being sunk by the Australians, but that is not how these things work. The reason Argentina felt empowered to invade the Falklands in 1982 is that the UK announced it was moving one tiny little Ice Breaker (HMS Endurance) away from the South Atlantic. In diplomatic terms, this was a 'please invade now' call and was interpreted as such. The purchase of 8 submarines that actually work tells the Chinese that Australia in extremely unhappy about their advances into the ocean beyond their shores and have only so much tolerance of such behaviour - that is diplomacy in action. So, well done to the Australians who decided not to be defrauded by the French. The French will go back to selling arms to anyone they can find - I am sure that if that delightful new government in Afghanistan show signs of starting a blue water navy the French have some spare submarines available at bargain prices.