I bought all the Charlton Heroes off the stand when they came out, except this title, since I don't enjoy Bill Fraccio's art. I don't remember seeing the last two issues, which may be quite rare and are not yet on this site. #49 had a costume redesign by Dave Cockrum and #50 has the first professional work by Roy Thomas, who, when DC bought the Charlton characters, returned to the character briefly for the 'DC Challenge' miniseries. Looking forward to seeing these issues on the site.
Link to the book:
Mysteries of Unexplored Worlds 48