Yes the ball joint problem has been resolved but this was no great problem and very cheap to fix.I would go for the 1.6hdi unless you crave the extra power much better engine and the cam belt live is much much longer.as far as the tyre sensors are concerned they are problematic on all cars best to have them disconnected or buy a car where they are not fitted.I am on my second 407sw 1.6hdi its quite new and very low mileage the first did over 100k miles with I litre of DPF oil required .Plenty of second hand ones about in the UK but very few that have not been used to go round the world twice.