There's absolutely nothing wrong with the standard GT brakes, especially the Spec B 17"/16" vented set-up. For the street all you need is some good pads and you're good to go. You could go a little further with higher boiling point fluid, a master cyl support, and braided lines if you wanted to as well. That would get you a very capable street set-up that could even handle a beginners track day. Of course they look as good but it depends what you are after.
If you plan on tracking your car regularly then the Brembos would be an upgrade. However, these are OEM Brembos not not their high end aftermarket race brakes. You still need good fluid and pads. If you are really serious about tracking then you might want to look at AP, ENDLESS, Willwood, Alcon as well just to name a few but be prepared to dig really deep into your pockets. Here in Japan the entry level Endless models will set you back nearly AU$7k. Prova's Brembos are about the same.

