I used to have non ajustable Rancho's on my SPOA Sierra, I might as well had blocks of wood under there. It would throw you around, i had to go in !st on most dirt tracks and my missus would come for a drive coz it threw here boobs around too much

Ive had my Doetsch 3000 Shocks on all for corners and I reckon they are great!
Most of the forums that dont like them say that they are too soft. Then when you read down you find that they have them on big heavy Jeeps and F series trucks. I think they are perfect for light sierra's.
I measured the flex of my zook with no shocks in and just ordered the right length to suit. The only thing i had to add on was a little spacer on the mount coz the rubbers were squashed a little too much.