I haven't grown either but 'Radicans" is supposed to produce less bronzing in winter. Note that both can grow to be huge. Read the label and don't plant really close to your house.
I need a clarification about a response Is container grown better than balled in burlap?
In my view, container grown will establish better if you unwrap the roots and spread them out at planting time.
If you want a large one you probably have no choice but to go b-and-b. But it will definitely take longer to get established, and therefore require more care during that time.
Balled and burlap in the larger plant sizes often do not have as good of a survival chance as a container grown one. I just went through this with a client that had her heart set on 12 foot Leyland Cypress. I advised her to go with an 8 ft one in a container, especially since she wanted 6 of them for a screen. Also, the dirt ball can come apart on some of the larger b andb if not freshly dug. I had this happen in my own garden with a 5-6 ft Cherokee Princess and a Stellar Pink Dogwood. Come to think of it, they were from the same nursery. One died. With a fast growing tree like a cryptomeria, I would first attempt to find a container grown one. Enjoy, they are gorgeous trees.