Does she like working on math problems?
If so, I might try picking up one of Singapore's "Challenging Word Problems" workbooks for Level 2 and let her work one each morning or something.
That way you'll know if there are any major gaps before she starts, and if that one is too difficult, you can always jump back to the Level 1 book.
This way she can use a variety of strategies to solve, and the problems are more like fun puzzles than drill.
(All of that to say that having seen bits and pieces of EDM over the years, I would share your uneasiness.)
