Here is how I learned how to pronounce Radice: I was hanging out in my local cigar shop, smoking my Radiss, when a sales rep from some cigar company stopped by. He saw right away what I was smoking, and asked, "Is that a Radeechay?"
"What?" I asked.
"Is that a Radeechay?"
"Oh, yeah, it is."
Turned out that he used to work for a (or the) Radice distributor (Ashton?).
I am really not sure how my brain picked up on his pronounciation as quickly as it did, but I dodged that stupid-bullet quite well.
Whew. I'm also glad that I never had to say Radiss out loud, never having to tell someone what I was smoking.