I have a handful of polyurethane bushings on my 07 WRX and I was always warned that they would make my ride "harsh." So far, it has only been noticeably stiffer, but far from what I would consider harsh. Moral of the story: do not fear the urethane.
+1 urethane. It's stiffer which gives a feel of more connection between drivetrain and car. The driver almost always prefers this connection above the smoothness of being disconnected from your car. Passengers will notice some additional movement when shifting but it won't be that noticeable. To a driver? All benefit, no negative.
I had a FULL Energy Suspension kit on my Civic way back in the day and have nothing but good things to say. When I bought it pretty much every bushing was wasted! I never had any squeaks from them either.
Yeah it sucked doing my Civic. I had to use about 10 cans of WD-40 and torches on 3/4 of the car. Then strip it all down so there was no lubricants on there before installing the poly bushings. Wasn't fun...