So, I've seen the GTO anime and the original GTO series. Aside from the actors (because I know you're a huge Shinkawa fan), is there any particular reason why I should watch GTO 2012? What do you think it did better? I loved the chemistry between Sorimachi and Matsushima in the original.
I've also seen the GTO anime, probably some time during GTO 2012's airtime, and I find that GTO 2012 followed the anime closely. they actually took the episode from the anime where Onizuka smashed down the wall with a sleigh hammer. they even made Onizuka do the GERMAN SUPLEX on Uchiyamada instead of the drop kick Sorimachi did in his version etc.
not sure if they followed the original manga closely as well, but GTO 2012 was also based on GTO Shonan Days where they threw in students from there with the students from the original manga. oh and Uehara Anko (who was portrayed by Shinkawa in GTO 2012) didn't exist in GTO 1998 since she was merged with Miyabi's character. however, GTO 2012 made them two separate characters just like the manga/anime. I don't think they left out or merged any characters in the 2012 version either.
note: I've never seen the 1998 version but I did read a bit about how it didn't actually follow the manga, but still kept its spirit.