Skyjacker leaf springs had a bad reputation back in the day for sagging quickly and they would not warranty the springs. I don't know if they have corrected this issue or not. I know they sagged a lot when I put their 4" springs on my '88 yj.
I've never heard of Skyjacker riding stiff, as they ride quite well when using their hydro shocks. You'll get a little more of a harsh ride using their Nitro shocks or gas-charged shocks of another brand.
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