Quoted in 100% agreement.The short answer is 100cc and a badge. (And a different drive)
"better" for whom?
Drifters find the GTS "better" for their purposes as they don't want 4WD.
They have different images, different purposes, different availablity and different prices.
You can achive the same results but you get more BHP on a GTR for less £.Even though the GTR has alot more features and the general speed is better, which one,(GTR or the GTS-T) is more customisable, for basic power improvements such as BHP, 0-60 etc..