Pro-Kit right height at each wheel
 

I recently installed pro-kit springs on my BRZ and last weekend put on 18" wheels. When I go around each wheel to check the drop, I can almost perfectly fit 2 fingers in all wheel-to-fender gaps except the drivers side rear--this wheel seems to be slightly lower. Does anyone else have this issue? The passenger side rear also seems a hair lower than the passenger side front.

Best bet would be to take a measuring tape to it. I had the same issues with my Sportlines. My rear passenger side sat considerably lower than the rest of the car. Most Pro-Kits I've seen seem pretty even. Take a measuring tape and see exactly how much of a difference you're talking about here.

Just throwing this out there. Did you make sure that the spring was sitting in the rubber piece the same way the old spring was. If it wasn't in that pocket where the spring ended I could see them initially sitting a bit higher making the others look lower.

Yes, and I can't see 3 accidentally slipping out and only one staying in the right spot. If I had one higher than the three others then that could be possible.