Correct! There are quite a few differences from the original Thunderbirds. The originals were neck through construction and many suffered from neck dive. The studios design tackled those problems with many changes. A good, more solid bridge IMHO, lighter weight construction. A more rounded body, smaller headstock and lighter weight tuners. It retains the Thunderbird vibe, signature sound and electronics. A very "cool" and nice playing bass.
I should say that I never owned one of the older Thunderbirds so am happy to be corrected.
I played one of the more recent Reverse Thunderbirds, which I liked. I and was looking to buy one when I found this locally and I had to have it. I am already having 2nd thoughts about selling as it would be difficult to find another.
The only other one I have seen in this colour was being used by the Molly Karloff bass player a couple of years back. He looked "cool as" but he is a lot younger than me and had more hair! He had removed the pickguard so it looked very red under the lights.