How tires effect handling on M5 E60

I changed all 4 tire on my 2006 M5 from a set of worn Continental ContactSport 2 to new Dunlop Sport Maxx GT tires.

Since the change I have run for 1000 miles. The ride feels a little more firm. The problem I have is that the handling seems worse than with worn tires. When I hit a joint on the road the steering vibrates more than I would expect. The traction control also seems to kick in more easily than before when taking off from a standstill and turning right or left into traffic. I have had BMW check everything and they say nothing is wrong with the alignment or tracking or suspension.

Anyone experienced similar results with these tires?

How many miles are on the car? What is the air pressure in the tires (front and back)?

52,000 miles. All tires are exactly at 36 psi as required. I have had both the tire company installer and BMW do balancing tracking etc. They all say everything is perfect. The BMW person tried to tell me yesterday that it is the hardness of the tires but I have no way to check this and I did not purposely choose this tire because of long life. It has a relative tread wear of 240 which is the same as the old tires.

I have had this car for 20,000 miles and you get to know the feel of the car very well. To me the difference in ride and handling is enough to bother me, but the garage want to say it is relatively "normal". Maybe they are right.