Well I love the California's handling. Even without tuning it. It was actually a very nice surprise. It feels very balanced in terms of weight, and it just turns in. Without having to resort to big camber, toe and other tuning options.
And when it looses rear grip it power slides nicely.
Maybe it's a bit too much if you are used to run the cars on understeer, but I personally love to be able to turn it in and just worry about the rear grip.
Come to think of it, It may be the only car I drive with 0 or near 0 toe.
But I don't have a real fast tune (only a fast/fun tune), so I will try some of our tuners too. I just can't spend all that time fine tuning a car online