I find it interesting that the IIHS hung their hat on the 4 door PT cruiser while having no data related to the 2 door convertible.

Your comment is bang on

This is simply a subjective opinion not founded in fact. I have owned both the vehicles under discussion and found both of them to have their quirkiness... but neither to be awful as you stated.

The PT cruiser has nothing in common with the Neon, save the engine and transmission which is also true of the Sebring, Caravan etc. The vehicle platforms are completely different. I own both and know the difference very well.

The CAN buss and integrated power module, is a Bosch design added to all Daimler Benz vehicle platforms, starting about 2004 for Chrysler/Dodge/Jeep products.