The following question is taken from a JLPT N1 grammar/expressions prep book:
１ 中といわず外といわず ２ 中といっても外といっても
３ 中はともかく外も ４ 中外もかまわず
In the book, no. 1 is listed as the correct answer, but no explanation is given. I've asked my Japanese teacher why, but she was equally puzzled. To me it seems nos. 1, 2 and 4 are all equivalent or have the same meaning.