I haven't completed my Jedburgh yet, but I will be using a Gen X Global XVSN mask. Because this is the only time I will use the mask, I picked it because it was cheap, but still had favorable reviews. I will let you know more about the mask once it's been used.

http://www.amazon.com/Gen-X-Global-XVSN-Paintball-G-302/dp/B0054WMMQO