If the trademark owner can prove bad faith on your part, that you have used the name in a misleading or confusingly similar way, the hyphen is really not going to make a difference. Also, remember that trademarks need not be registered to have legal force if the brand name has been used in commerce in a way that establishes a common law trademark.
Disclaimer: I am not a lawyer, simply an ordinary person expressing his view from information he has read on the forum and elsewhere. This is not in any way or form whatsoever legal advice from me. Always consult an attorney or qualified professional.
