They are sourced from the same land.
They perform the same, however dont last exactly the same.
On a Fiero, the Jap ones would last a good 10k kms under real hard abuse, this one will start fading away at around 8k kms. These plates would hold over 22 horses on my Fiero 200, its just that I would change them every 3k kms.
The RTR plates are also not jap, however they last a solid 25k kms under whatever abuse u throw at it. My RTR has clocked 22k kms with plenty of racing abuse and still runs on OE plates and still pops thru gear shifts and not a sign of a slip yet. Its got the best clutch in the country.