Weird, I can't remember ever putting a bad thing on my car, or rather, something I ended up hating. Just about everything I've put on has worked, aside from my AVC-R giving me problems, but that could be due to bad vacuum routing haha.
I have the Ebay engine torque damper and I noticed a difference right away.
I have the padded console box in place of the ashtray and I LOVE it as well (everything you put in there is more accessible and it seems like there's more room).
I love the RE VMIC (I don't even run my fans anymore, at least while I'm moving haha, and my intake air temps are pretty low too)
The GReddy Ti exhaust (super light and with a nice deep tone)
The STANCE coilovers (kinda stiff on bad streets but I deal with it)
SuperPro bushings, RB sway bars (much stiffer with sway bars and bushings are quiet and ride great)
Power FC (so easy to use and my tuner is still amazed how much you can do with it, I was his first PFC and he can't wait to tune more haha)
Single turbo (GT3767S, .70 comp and .68 turb) spools amazingly fast and I have a nice smooth powerband.
Enkei RPF1s, they're so inexpensive, light, and look great too.
Things I don't notice so much, good OR bad, are the toe links and trailing arms, fuel kit (you won't really notice til something goes wrong haha), Twin Power (same as the fuel kit).
I've do and have done quite a bit of research before I get something so there's a better chance of being happy. It's worked out pretty well so far.
My cardomain...
http://www.cardomain.com/ride/719631