I'm doing engineering at ANU. We have a relatively small number of students compared to UNSW and Melbourne (about 250 this year, mostly locals) but I'm pretty sure our program is just as good! Engineering at ANU is actually a systems engineering degree - you get to major in one or two areas that you're interested in but you also take courses outside that area. I think it's great.
We also have a engineering reseach and development scholars program (for people with UAI 98++) in which you get to conduct your own research in a field that interests you with the guidance of a mentor (one of the lecturers).
Oh and our fees is significantly less than that of UNSW and Melb Uni
The downside to coming here would be that there's nothing much to do in Canberra. Haha. But hey, ur here to study so I guess that's actually a good thing. And Sydney's only 3 hours away if u ever need your big city fix

Well I can't really tell you how it is compared to Melbourne and Sydney since I've never done Engineering in those places! But I certainly do think that we have a pretty good program. I guess many people don't come here because Canberra city isn't exactly as appealing as Sydney or Melbourne...
Umm to answer your question, ANU has a pretty high employment percentage for fresh graduates I reckon (similar to Melb Uni in terms of percentage). I can't give u an exact figure for the average salary of a fresh grad but I should think it's not too bad. Really, if you're prepared to work hard, I'm sure you won't have a problem getting a job.
U can PM me if u need more info on anything else