I don't know really - the desert scenes, in the right light, did look lovely, but there was very little going on throughout those desert sequences. I personally would have preferred a bit more cash thrown at some action or something to break up that big chunk of time rather than sitting there thinking "Oh, it's a bit boring but it looks pretty". I don't know...I'm sure they had honest enough intentions, but can't help but think they liked the idea of shooting abroad for the sake of it.
I think the New York excursion for the Dalek two parter was something that you could really point a finger at for wasting money though. Now that clearly was a piss take - filming a few little bits to throw into the episode. I don't know how many people went off for that, but I recall the Confidential episode and it seemed like there were more people about then needed (I mean to be honest - surely they could have gotten away with a producer and camera man).