Yes, the upper decoder is a Paragon 4 that I got last week and the lower one is a Paragon 3 decoder I pulled out of a light 4-6-2.
The only difference I can see between the two is the Rolling Thunder antenna is visible on the P3, not on the P4, wonder if the switched it to the bottom of the decoder, it looks like it is mounted in a through hole.
Have both P3 and P4 steamers and the P4 is much improved over the P3. My only complaint is the chuff timing is nowhere good as ESU or Soundtraxx. They have no parameter to compensate for gearing. On my Mikado, it is pretty spot on, but the the Pacific's vary quite a bit with throttle input, from too slow at low speed to to fast at high speed. They are too used to the HO models which have hall effect sensors on the drive line so they don't have to worry at all about fancy algorithms to keep time.
