Disclaimer: I loved the original GTO, I genuinely think that it's a top 10 manga of all time. Hell, even I REALLY liked 14 days in Shonan. I think writing reviews is a waste of time, but reading this pissed me off so much that I feel like it'd be a sin not to.
Story: 4/10
Onizuka is now in prison and is retelling everyone how he got there. Simple story, nothing too serious and complex. However, I feel like it really lost its "heart"-- that certain something that really made GTO special.
Art: 6/10
Was never really a fan of GTO's art in the first place, but I grew accustomed to it as I read more and more.
Characters: 4/10
This is my main problem with this story. The characters in the original were assholes to a degree, but they were pretty likable. The student-teacher interactions between Onizuka and the students were great and wholesome. You could really feel them changing and slowly warming up to Oni. However, they scratched everything away in Paradise Lost. It seems like the only thing Onizuka has to do is solve one life problems for these students and they magically just love him. There are barely any interactions between them, too. It's like they get an arc, then they're kick out the story. Onizuka's likableness is still there, but he makes some moves that made me question, "Is that really how Onizuka would act?" Everything built in the original was thrown out the window. They added more time with Uchiyamada (which was surprisingly fun), but kicked Azusa out the story. Like wtf happened? Overall, biggest downgrade from the original.
Enjoyment: 5/10
Humor is the same, but suddenly became explicit. I mean, I'm kind of a degenerate too, so I don't mind ecchi and smut, but the transition was pretty weird. However, just because some parts were pretty funny, it doesn't really mean that I enjoyed the whole ride. There are some pretty boring arcs and sometimes they focus on unlikable characters.
Overall: 5/10
Would I have picked this up if GTO never existed? No. Do I appreciate GTO still being published? Yes. However, I can't lie that this is a downer compared to the original. It lost the charisma of the original GTO and it would be an understatement to say that I'm just a little disappointed. I'm VERY disappointed. This won't really affect the original's place in my heart, though. I WILL always love it and will re-read it within a few years' time.
