Actually, coasters with steel rails on wood structure are 100% wood coasters...Again the structure has nothing to do with determining the type of coaster...In reality the only true hybrid coaster that I am aware of would have been Son Of Beast...The loop was all steel making it a coaster that had actually wood and steel tracking according to the definition...However, it's not to say that the definition will one day change..But as of now the new TG will be classified as steel...Also, I believe it's going to be a very good coaster and if it works their are many coasters out there that should have this done..