This is quite fishy. I actually have both the Huawei Y300 and Xperia M. But I think the Xperia M has a much better battery life than the Y300. Even from your test it shows that the Xperia M has a much brighter screen meaning that it uses much more energy.
But anyway ,its probably because the stuff that I can do are much more when using my Xperia M per time is much more than the Y300.
Pocket-sized Samurai. Sony's latest member of the Xperia series features a relatively small screen of only four inches. The low-clocked dual-core processor is however supported by a strong graphics unit. Is that enough to gain a foothold in the entry-level sector?