Class hours for UNSW are pretty much the same as the ones I quoted for USyd, ie 20-24ish, transport will generally be 15 mins longer if you're going via central, but if you're in the Eastern suburbs it'll probably be less than for USyd.
The subjects for the first two years of the UNSW degree will be more generalised as all students in the aerospace, mechanical, mechatronic, manufacturing and naval engineering degrees have a common program, an at the end of second year you choose your discipline (ie one of those five streams I just mentioned), and the remaining two years of your degree are spend specialising. This has both its benefits and drawbacks, namely that it gives you longer to decide that you might prefer to do mechatronics in those two years being a benefit, but a downside is that the course might seem too general to you in those two years and you won't get stuck into the really meaty specific mech stuff until third year.
The subjects at UNSW differ from other universities in that they have a certain number of general education units to be completed across the course of your degree, and this means you must take a certain number of units from either the arts, science, commerce or law (I might've missed a faculty) faculties (ie any faculty not your own), while USyd offers an opportunity to do this you can also choose to fill USyd free electives with some engineering electives. I don't know an incredible amount about the UTS degree, but I do know that with all engineering degrees there you have to do a diploma of engineering practice, which means you spend two semester long blocks working in industry, and this will mean your degree takes a year longer than at UNSW/USyd. Again, this has advantages and disadvantages, examples of the former being that you get a better chance of having a job straight out of uni with the company you had your industry experience with (though there is also an industry experience requirment at USyd and I'd assume UNSW, it's not as lengthy), and the disadvantage being that your degree takes five years instead of four.
Formula SAE participation in first year isn't going to happen at any of the three unis as far as I know.
I think I've babbled enough for now, here's some links to the relevent degree outlines at the three universities, and hopefully someone in an amme degree at UNSW will be able to post to give you specific details about the course there.
http://www.handbook.unsw.edu.au/undergraduate/plans/2005/MECHA13710.html
http://www.aeromech.usyd.edu.au/6cp/AMME_6cp_2005.html#mech
http://www.handbook.uts.edu.au/eng/ug/c10061.html