Hi,
First post here, be gentle
I happen to have both an SH Subaru Forester and a KJ. Just for the record, the Subaru is open diff both front and rear.
The KJ got DTTs both front and rear. The "return-to-center" urge was quite heavy the first probably 100km, then it "relaxed" a bit. It is still there, but I got used to it. Also, on high friction roads (asphalt, concrete), I sometimes have the feeling the car initially resists the attempt to turn, and then almost over steers and drags you in the turn, but this might be because I've also put spacers which change the way the tyres move when turning.
Off road, I'm very happy with the Truetracs, especially when climbing dirt/gravel -- definitely less wheel spin and you can control speed better. I'm not into extreme off-roading, though, so I haven't tested and I don't know whether they will be of good use e.g. in deep greasy mud.
As mentioned above, minimal traction is needed for the DTTs to work. A tree took away the KJ rear left taillight just two days ago because the car slipped and bumped into it after spinning the rear left tyre on one of its snow-wet roots (so small you wouldn't be able to trip on it otherwise). The right tyre did not spin at all, as if I had an open diff. So, one thing proven for a millionth time -- LSD or not, if you have winter, get winter tyres