I used Eibach Pro Series springs on mine with regular ol' Monroe Struts (OESpectrum).
After install someone on here advised that Monroe makes terrible struts and I should have used KYB instead. Besides not tightening then down enough I've had zero problems though. Take that for what you will. From what I've read here and other places using lowering springs on OEM or less then struts is much harder on the strut and the struts will wear out faster because of it. Still, it's the most cost effective way to lower the car.
With the Eibach my back looks lower then the front which I think is due to the fact they are made for the Eclipse so the coils drop the front and back an equal amount. Not sure if something like the Megan springs made for 9G's make a more even looking drop or not. To guarantee an even drop you can really shell out some coin and get some coil overs instead and manually adjust the drop to how much you want. I personally went with the Eibachs over the Megans because I didn't want to completely bottom out the car and the Eibachs drop seemed to be just right to me. I heard/seen the Teins look really good too.
That's my nice answer, but for future reference if you search the forums here there's TONS of posts on lowering 9G's and with what. In fact, if you search you can see a lotta great examples of 9G's lowered on different combinations of equipment. That being said I gave you a nice answer because I too, didn't search here and first posted near this exact same post as did many others before me.
Not the best picture to see exactly how low the car is, but here's mine for reference.
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