When you export out of After Effects, use the same codec you are using in Premiere Pro. That way no rendering will be required in Premiere Pro.
I use the Microsoft DV codec. Some people would use the Canopus codec, for example. And when I create a project in After Effects set for 720X480 using a Pixel Aspect Ratio (PAR) of 1.2, it comes out widescreen. Then when exported, and imported into a widescreen project in Premiere Pro, I don’t have to render.
Steven
Adobe Premiere Pro 1.5.1 / After Effects 6.5 Pro https://www.stevengotz.com
Learning Adobe Premiere Pro 1.5 https://www.lynda.com
Contributing Writer, PeachPit Press, Visual QuickPro Guide, Premiere Pro 1.5