Hi Andrew,
You're about 5months too late! I was at Sydney but after weighing up the pros and cons of both universities I decided to stay at Macquarie. In answer to your questions:
1) I had both jurisprudence and law, lawyers and society credited.
2)Had I stayed there, I would have finished at the same time as everyone who had started at Sydney immediately (ie It would not have taken me any longer to finish my degree than it would to finish at Mac)
3)I would have had to complete 2 extra non-credit based subjects (Legal Research 1 and Legal Research 2) but these are light units designed to teach you research skills.
4) I don't want to share my GPA or UAI on BOS but I'll tell you my UAI was slighly higher than yours and my overall average was a distinction.
Transferring generally
At the time: Felt very out of place (Sydney Law people are not friendly though there are admittedly a few exceptions), had about 3 times the travel time, no ilecture (lectures weren't even tape recorded so if you missed them, you REALLY missed them). Also, I am an Arts/Law student so I was very interested in English there and at the time didn't find English there any better than at Macquarie.
Assessment also tends to be more sit down exams rather than take home exams for law.
Looking back: There were more friendly people than I remembered, Criminal LAW was UNQUESTIONABLY better at Sydney so if you intend to specialise in anything to do with that and you can transfer, TAKE IT! Also I have discovered that there is a variety in quality wherever you go. Contract LAW was not necessarily better at Sydney but as I said Criminal Law definitely was. The English unit I enrolled in last semester at Sydney was of average quality but I'm now doing cross-institutional study so I can take a Fantasy literature course at Sydney.
If you live close to Sydney/ travel is not an issue you for you, the move is probably worth it (I live 20 mins from Macquarie and 1.5 hrs away from Syd so it really mattered to me). Also, Sydney has a good social justice program which I didn't have the chance to appreciate until I had withdrawn. Another important issue to consider is that the amount of work required for law increases enormously in second year wherever you are, and I didn't know this at the time (I thought it was just Sydeny students). In fact, I think I actually had more work for contracts at Mac then I was doing at Sydney!
In short, Sydney is more prestigious than Mac and has better social justice oppurtunities but other than that, I couldn't detect a major difference between the unis in respect to law (except criminal law). Tutes were bigger at Sydney but I've noticed that they've been steadily getting bigger at Mac too. Honestly, my main reason for withdrawing was travel but I'm still considering transferring at 3rd year (if I manage to maintain my average).
If you have more questions email me. Goodluck!