Sounds to me like maybe whoever did your king pins has reamed the bushes a little on the snug side and you have a bit of stiction. It took me about 200 miles and three adjustment sessions before I got my SSL setup to settle down, but it's been fine for 7 years now. Remember to do your adjustments ideally with a couple of sacks of spuds on the driver's seat to simulate the driver's weight as much as you can. It's important to make sure the adjustment is the same both sides, I made up a little spacer block to check
On a 4/4 on 165 tyres I would recommend going for the low ride height option with the spacer below the stub axle and with the rebound springs set slightly slack. This gives me a nice compliant ride over bumpy B roads (we have plenty of those in Gloucestershire) and I don't mind the slight additional roll on turn in to fast corners because we don't have many of those.
