I haven't seen any Maidens conversion around, but I have seen conversions for Lavendar & Lace's Celtic Summer, which used the Needlepaint. Maybe you could try finding this conversion by asking around on different boards (TWBB or the L&L board), and hopefully, you'll find someone who could help.

As for the Wisper, it's fluffier than regular DMC, but you could easily just stitch with regular white cotton floss if you want.

Hope that helps. Happy stitching!
Cindy :)