Nothing wrong with polyurethane as long as it's installed properly.
That said, I install adjustable strut rods and greaseable pivot pins when I install poly LCA bushings, because the poly LCA bushings don't have as much give as the rubber bushings and therefore the LCA needs to be located more accurately than the factory did. The factory strut rods are a "one size fits most" kind of deal, which is to say that they're not right for anyone, just "close enough". With rubber bushings there's enough slop that there's some forgiveness, with poly there isn't so the LCA really needs to be in the right spot, not just close enough.
If you're keeping the stock upper control arms, buy a set of Moog 7103 offset bushings instead of standard bushings. That will allow you to get more caster when you set your alignment later.
If you install torsion bars much bigger than 1", you will want a
GOOD set of shocks. Bilsteins or Hotchkis. Running cheap shocks on large bars will make you miserable. I know, I did it. I run 1.12" Firm Feel torsion bars on my Challenger, and the difference between those bars with a set of KYB's and those bars with a set of RCD Bilsteins is night and day. The Hotchkis shocks are even better, I run a set of those on my Duster. It also has 1.12" FFI torsion bars, but they're a bit stiffer because of the shorter length.
Get a good alignment when you're finished. And by good I mean NOT to factory specs. Factory specs were for bias ply's, and are wrong for radials of any kind. You should be looking for something like -.25* to -.5* camber, +3 caster (or more if you can get it), and 1/16 to 1/8" toe in.
The moog 7103's get installed like this for more caster...
