No. The built-in radio transmitter option for the Sekonic flash is for use with PocketWizard brand triggers. Canon uses their own radio system. The 478DR can still METER the flash... but you'll have to pop the flashes manually (and the PocketWizard waits for the burst of light and measures that.)
I own a Sekonic 758DR -- same thing with that model.
There is if you have studio mono-lights with Pocket Wizard radio triggers.
If you are using only Canon radio-technology speedlite gear (600EX-RTs and ST-E3-RT) then there's no point buying the Pocket Wizard module.
On the Sekonic 478, you can opt out of the Pocket Wizard radio and if you change your mind you can add it later. It's actually just a small module that fits in a compartment on the back and they sell this module as an accessory -- they also sell spot metering modules as accessories for the 478.