Just a quick FYi -
I have been down this road before, and I have first hand experience. A company does NOT have to send you a C&D letter. In my case, they simply filed a WIPO complaint (without telling me) and the next thing I know my registrar locked my domain up tighter than a drum. The whole process took over 3 months, and ultimately I ended up transferring the domain to their account.
Also, simply adding a word to their company name, ir NOT enough to keep them from suing you. The domain name had a related keyword appended to the company name, yet they still had grounds.
This has only happened to me once, but I have gotten several C&D letters over the years, Ebay and MS are sticklers for this
My advice - stay away from trademarked names