I believe you mean Realta is "powered by Teranex".
Also, Silicon Optix is the company that makes both the Realta and Reon chips. Teranex was purchased by Silicon Optix and is now a division within SO, and its technology (hardware platform and video processing algorithms) is found in Realta, not Reon.
Since Silicon Optix was a spin-off founded by ex-Genesis employees, Reon is probably based on older Genesis technology. Since Genesis owns the Faroudja DCDi technology, I wouldn't be surprised if Reon is similar in performance to Faroudja DCDi. (Don't quote me on this though!)