CortexM toolchain recommendations

Hi toolchain gurus,

I am about to start some projects working with CortexMx devices and am wondering if anyone has an opinion on which toolchain(s) I should use/investigate?

Being a fan of Linaro, my first instinct would be to use cbuild2 to build an arm-none-eabi- toolchain from a 4.8.x tree. But looking around I can't help notice https://launchpad.net/gcc-arm-embedded.

Does anyone know if gcc-arm-embedded has things the Linaro toolchain doesn't wrt Cortex M0, M3, and M4 device/instruction support?

Best regards, Trevor