Default Can't root (3.62, stock)

Hey guys,

I've just received my replacement phone and I'm trying to route it.

It came with 4.3 already installed.

I've unlocked the bootloader and installed CWM but want to s-off so I'm trying to root my stock (Three UK branding) ROM.

I've trying flashing superuser an superSU from recovery (CWM and TWRP) and they flash successfully and install onto my phone but don't actually give me root access!?

It also won't let me update the binaries in SuperSU

Any ideas?

Thanks in advance.

Edit - I'd somehow managed to download an outdated version on SuperSU. It's working now. Silly me.