People seem to like tuning those lexus sc300s, and oodi s4s, and rs3s, and the bmuu //m cars, and the porkchas. hell even the cadavrelacs are popular with the dyno queens.
hope it treats you well. probably you'll dump it and move on to something else in a year or three anyways. maybe something with a manual? and less than taxi-cab weight? bmw makes some lightish manual luxury cars now don't they?