Well zeyad, in my opinion, i think that both phones are just as good as each other. Since the xperia m recently got a firmware update to 4.3, it has just been fantastic. If you look at it in terms of development, both phones are in the low activity section, i dont know why, but it just seems that way. So i would personally recommend the xperia m as it is 100$ cheaper, with no difference to the xperia l (except screen size and camera i think), and you definitely get value for your money.
Hope this helped
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