Just adding my 2 sens about the Maxis world unlimited data package. I've used it twice previously and it was actually pretty good. Never hit a limit, never really had a problem with it, and no unexpected additional charges on my Maxis bill (or at least any significant ones). I used it when I was travelling UK --> Switzerland --> Dubai and for these 3 countries it was pretty good throughout.

To be perfectly honest, I do think it is a crazy good deal - although I'm not quite sure why they are offering it because relative to other providers, the unlimited part of the deal is probably the part that is really good. But as always, read T&Cs

* Just to add, I think they changed the conditions slightly recently - now it is 2 GB high speed daily and reduced speed of 1Mbps after - although this is a reasonable speed to do basic surfing.