I think they're still good. I'm doing the new chem and physics too, and I've being using a LOT of old resources especially for physics. I used my friend's Matrix book from the old syllabus, since our Mod 1 (kinematics) was in their Year 11 syllabus too. Generally for physics, the textbooks should be fine since physics really doesn't change. It's the same concepts and information after all, physics really doesn't change. However, for the past papers I would be careful that they assess the same topics (inquiry question) and skills. Other than that, I would think physics is the same. Chemistry is a bit trickier, and I haven't compared the syllabus/notes a lot, but there are a few things that we go more indepth into (that the old syllabus didn't) so I think you would be able to use the textbook, just make sure that it is relevant and goes into enough detail.
