Before I head off to bed, I'm not convinced that you're convinced that special relativity is a good idea.
First, your teacher is obviously a great physics teacher if he is willing to teach Special Relativity. He's been able to look beyond the statistics, not be a sheep and teach you the better content. If you enjoy the kind of stuff in structures and materials, there's enough of that kind of stuff in motion.
SR is some fairly big ideas to grasp, but quite quickly you will 'click' and it'll all appear intuitive to you. You have probably heard of the concept of 'scientific beauty' before, it's kind of an odd idea until you really see it and understand it. When I 'clicked' and really got my head around it I finally understood what 'scientific beauty' is. Special relativity just makes so much sense, and the way it has been set out is brilliant. Contrary to what you may know of Einstein's work, e=mc^2 wasn't the part that I found most brilliant.
Answering questions is not difficult at all, to answer an SR question you just need to remember the 4 or 5 basic principles and with a lot of the exam questions you could eliminate 2 or 3 of the options pretty much immediately. The mathematics involved is ridiculously simple.
You really will gain a better appreciation/understanding for the work of Newton, Maxwell, Einstein/physics in general. The SR detailed study is pure awesome.
About the synchroton detailed study, we're studying sound so I can't really say much about it. But just because the Australian Synchrotron may close doesn't mean that all particle accelerators are going to close. If your teacher is one of those few teachers that is willing to teach Relativity, I would trust his opinion and just go with it.
Finally, from what I gathered, the only reason you want to switch out of Relativity is because the statistics have told you that more people do it and therefore more score better (in S&M). I've already outlined why relativity isn't as hard as you think (it is just VCE physics after all). If the only thing you want is an easy score, opt out of physics completely.Don't bother with it. There's better stuff you could be doing with your time. Physics can be quite excruciatingly painful if you don't enjoy it. I'm sorry if that seems harsh, but I find it hard to understand how someone could even consider the notion of rejecting the opportunity to learn about one of the greatest physics discoveries yet.
Maybe it's because you're not aware of some of the implications of special relativity.
Watch this: http://www.youtube.com/watch?v=A0jiY-CZ6YA. If that does not spark your curiosity, I don't believe anything in the physics course will.
I think I'm done now.
edit: fixed up my annoying spelling mistakes