need info from lifted tj owners

I have been shopping for tjs lately, and im wondering if im too picky or just don't know what I should expect from a coil spring lift with 35s...
two I have test drove now seem to have the same issue, almost like "bump steer" in a yj. Every bump seems to pull the jeep in one direction or the other. Almost feels like i constantly have to correct the steering to keep it straight. Any of this make any sense?
Jeep 1- 02 tj. Sport. 4" lift, 35" x-terrains. Not much done besides that. I did notice the real axle cover was recently resealed... dealer claims to have just recently replaced gears in the rear. (Seemed a little odd to me)
#2- 98 sahara. 4"lift skyjacker lift, 35" baja claws. Very clean jeep, throttle body spacer, cold air intake, custom front bumper w/ receiver, warn rear bumper and tire carrier, borla exhaust, one owner... point is, well maintained and even had paperwork from the shop that did the lift. But this one had the same problem! It even gave a little shimmy when turning and accelerating at the same time twice.
My question is... is this just the way they r supposed to feel? my yj seems so much tighter, but its leaf sprung, 33" tires, no power steering.... a lot of differences between the two, so I am starting to think that this may be normal after lifting a coil sprung jeep and dropping in 35"banana tires... any thoughts/experiences?

That makes sense... I didn't think u had to mess with caster on solid axles.. how can I check it, at the dealer lot mind u....
And ill fix the rest of my initial post when I get home, gotta hate auto correct! Lol

so, either way, it sounds like its mainly fine tuning. all trac bars and linkage that i could get to seemed pretty tight to me.... no major deal breaker in your opinions?? the jeep is cherry otherwise imo, of course there is some trail paint here and there, stuff you would expect from a 98. 103,500 miles!!! not a single drip i could see anywhere under it after the test drive....