Which would you buy Alcatel Idol X or Sony Xperia M2 Aqua?

[AC Question]

I am buying a new phone for my sister and I would like to hear your opinion. Idol X (6040X) is better in almost all aspects on paper, but it is already old phone that runs jellybean and won't get any updates anymore (it has kitkat 4.4.2. that has been pulled?). Xperia M2 works fluid, has great battery life and has developer support and it will have updates for some time. I am not into being up to date with latest software, but I am afraid that Idol X will be limited in a year or so. Which of these two will have give decent use for 2 years? Thanks