just totally a different car!
i mentioned it to my dealer who i love and who bothers to drive everything he can get his hands on... he agreed... interestingly he also commented that there is less of a difference in the 5 series sedan with and with out DH... but he just felt the weight, size and wheel base of the GT magnify the difference between dh and no dh.
2012 GT 550ix Msport (feb12)(ok early march 12)
09 X5 4.8
12 X3 35i (the wife)
61 356 roadster