SoulV: You are right there about bushes.
Firstly, I applaud you for changing your bushes. So many ppl always overlook this most basic of necessities when setting up their car!! Brand news super duper 39-way adjustable Tein suspension means nothing when you have crap and old bushes holding everything together. Every corner you take your wheels will end up pointing left right up or down, basically everywhere but where they're supposed to point, and your handling will be rubbish!
The thing about bushes is, everything is a compromise. In the OEM world, we're totally against PU bushes. When we were in R3, we made hard-rubber bushes. They were shore 90 hardness, against the standard bushes which are like shore 40. You may notice that TRD, Mazdaspeed, Nismo, etc all produce hard rubber bushes. Only the smaller aftermarket companies which do not have the capabilities or engineering to produce hard-rubber bushes will make and try to sell you PU bushes.
PU bushes suck. Bushes are designed together as part as of the whole suspension geometry package. Some of your suspension arms, via their bushes, are engineer to deflect a certain way under certain loads and forces. All sorts of engineering stuff is taken into account: bump-steer, compliance steer, roll centre, blah blah blah. Basically, stuff that I wouldn't f*ck with wei, as it could lead to downright dangerous handling. And yet, when you replace your rubber bushes with PU sh*t, you are doing just that: altering the complete dynamics of your whole suspension. I would highly recommend against that!!
I mean ok, to be fair, certain non-dynamic bushes like swaybar mountings and link bushes, can be changed no worries. But stuff like trailing arm bushes, front and rear lower arm mountings, and strut top mounts, I wouldn't screw with. These bushes are developed with certain "paths", which when you omit, completely change the handling of the car. Oh yes, you can go the complete PU bush or even better spherical bushes route, but you really need to know what you're doing. And that's what engineers like CQ are for. And since I don't know everything about suspension, I preferably wouldn't mess with my bushes. I always buy rubber bushes where possible. They're more expensive, but they're more consistent in their performance and handling of the vehicle.
/adian