i'm doing yr 12 next year, and i went to the library and borrowed a ton of book like; revise in a month, insight textguide, checkpoints, a+ notes etc. and i just wrote down a few pts that were really important and returned them
e.g. one of the insight text guides for 'the player' was really good, so i just wrote down the stuff that would actually help. the english checkpoints 2010 had some really good oral pointers etc. but the rest of the book was useless.
i personally am not buying any commercial study guides, because if you rely on them too much you don't learn the stuff as best as you could -> e.g. just using the stuff from a textguide isn't that good, because chances are a lot of other people are using those points, but if you get your own ideas, you'll probably be able to write a better quality essay, however, sometimes the insight guides are a good way of getting started and then developing your own ideas from there.
this is just my personal opinion, and i know a lot of people probably don't agree

in terms of lecturers, i don't think they are always worth it, it really depends on the person you are, for me i find it difficult to work at such a fast pace and i usually get very lost, but other people can work at that pace and they may benefit from them, so overall it really is up to the kind of personyou are
hope this helps
