The last time I was here, we could not root 4.3 without either unlocking bootloader or root 4.2 first. Don't know if things have changed since then? Now there is a new rooting app exploiting a newly discovered vulnerability and I wonder if it would work with the Xperia M on 4.3.. anyone tried it out yet?
LG GW300 -> Javaphone without touch
Dell Streak 5 (DSC 2.3) -> The original Phablet
Sony Xperia M (Stock)
Cubot X6 (Stock, fck mediatek)
B&N Nook HD+ (CM10.2)