Well, ever since I knew about the dreameye when it was released I was wondering why it had the blue swirl if it did not see any eurpean release...
There are some that have no swirl at all. I have one like that and another with an orange swirl. There are also two different box designs for the japanese release. Yakumo
At to the different models: HKT-9400 is the DreamEye itself, it's labelled as 9401 on the standard white and grey line Sega peripherals box, and as 9402 as the DreamPark edition (they come with different softwares). Also, the mic that comes with the DreamEye is different from the standard Alien Front/Seaman/etc mic works the same but with a different max/min frequency (can't remember which is higher).