I've been told my more than one ANZ Captain that the GE's are proving to be more economical on the long sectors and also able to get them up to cruisng altitude more quickly....
Is this born out in fact? I do know that the Rollers have been updated on some airlines with new Trent cores and the like.
ANZ's newest 744s - SUJ and NBV/W are GE powered. The older RR fleet are ZK NBS, T and U. I have been on all the lot at some stage and have been able to detect a hint of 'newness' on the more recent planes - as well as some grubby experiences at times particuarly just before the new spacemaker seats were fitted.
Can't see why anyone would fail to trust the American engines....
Really sorry that I'm not flying with them this year..... it's BA/QF all the way this time. Also, don't forget that ANZ do contract work on PW JT8Ds and similar at Christchurch. I had the pleasure of looking over that facility a couple of years ago. very interesting - especially being able to look inside the business end of a CF6! Didn't realise that they write the numbers of each fan blade on them.