Short answer: yes, things will be fine.
RC4, MD5 and, in some minor measure, SHA-1 all have some known shortcomings, but none of them will make your Web site weak. To be accurate: if using a RC4-MD5 cipher suite makes your Web site significantly weaker, then it is otherwise extremely solid -- more solid than seems to be practically reachable, indeed.
However, you might want to throw in a few more cipher suite, e.g. with support for 3DES and/or AES, so as to accommodate restricted clients. Some people got the messages wrong, panicked, and deactivated RC4 altogether from their browsers.
The "score" in ssltest is nigh meaningless. Don't read too much in it. It is like reputation in security.SE: it more relates to the efforts invested in obtaining a high score than to real security.