For resources it really depends also on the price you are willing to pay. As many of the tutoring centres have lessons that go for 3 hours and therefore are fairly costly. I had personal experience going to Matrix during the last term of year 11 and most of year 12, and found that they had good resources (but mostly the homework booklets are helpful), but in terms of the content resources I wouldn't say it was far superior than other notes or information I could find in a textbook or the internet because the content in high school is only so advanced to a certain point (there is a lot of repetitive questions even in sciences that if you learn how to do once you can do most questions) and also the books have a lot of blank spaces which is intended since the questions are covered throughout the lesson, but that means it will also depend what teacher you get and how detailed they are willing to go into the content.
On the other hand private tutoring I would say in terms of the resources it will still be fairly similar if you seek out a tutor who is experienced in the topic (very important since the syllabus for the chemistry and physics has changed so I would really recommend you find someone who is doing the subjects at uni or has some type of proof they know this content before, because I'm currently tutoring these subjects and from personal experience I can say the changes to the syllabus are quite extensive (although a lot of the core ideas are still present), there are large changes in terms of areas like addition of entropy, thermodynamics, NMR spectroscopy (also spectroscopy in general) removal of option topics which means some content in the option topics before is now a core topic (where not every person in the past would have completed all of the option topics unless they are studying the course at uni because these topics in the previous syllabus were not covered at all. But are introduced in universities in depth during first year chemistry and physics courses.
In terms of going ahead that far to do year 12 content I don't really think there is any large benefit the person is going to gain by doing that. Sure if you are interested maybe have a read of a bit of the content or watch some videos on youtube to get a basic understanding, but there's no need to go full on straight away because you need to remember these senior years are a marathon rather than a sprint and consistency is more important than trying to rush everything to get ahead, because any of your assessment tasks at school will be on content that has been covered up until that point in the class, so it's better to understand things in depth and being able to apply the content to questions rather than just knowing the information
