PID temperature calibration improved HIPS print

So I was able to improve my print quality by doing the E-step calibration procedure somewhat described here:

https://ohai.lulzbot.com/project/extruder_calibration/calibration/

I was using PLA at the time and things looked good. I switched back to HIPS and did another E-step calibration but the values held so no change was needed. I did noticed that the vertical faces had odd ridges in them. I showed my print PLA and HIPS prints to the local 3D printer brain at work and he suggested doing the PID temperature calibration found here:

I tried it out and my HIPS print and now it looks nearly as good as my PLA print. The results are below.

I should add that you enter M501 to get the current PID settings. Here are the before and after calibration values:

Before : After calibration
Proportional error gain: 28.79 : 28.56
Integral of the error gain: 1.91 : 2.06
Derivative of the error gain: 108.51 : 99.22

This seems like another new owner calibration to do before getting busy.

Nice looking PLA print:
Happy_PLA.jpg
Not so nice looking HIPS print
Bad_HIPS.jpg
After PID calibration: