Isn't it a
credit average to stay in adv. science? I'm doin' it.
Otherwise, I shouldn't see so many people in my classes.
It really doesn't matter as much whether you're in adv. or normal. You can still do advanced courses in normal science.
But, in advanced units... You also get the option to do special stuff (if you like the subject, you'll enjoy it).
Otherwise, there's the associate bonus of knowing friends who can help you plus some scaling in certain subjects.
This especially goes for labs. People in advanced streams will be more inclined to stay and contribute to group instead of buggering off at the first opportunity (hint, hint.)
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But, coming back... I'd say combine the two, as you can still have your advanced stuff.