Well apart from FMGC profile and your altimeter, seeing as others haven't mentioned it..... Airspeed? Profile and height are all good but not if it puts you over the threshold at 250 knots. And I have seen it happen all good in LNAV VNAV then wondering why we are still 250 knots at 16 miles at 5000ft, hmm seems a bit hot and sure enough suddenly reverts to speed mode and drifts above path because of an unable next altitude message suddenly appearing. These approaches are good overall, especially to ports with limited aids but still a trap for the unwary.