My concerns are she has never done narration and very minimal dictation. I'm wondering if Preparing has a gentle intro into that or if it just starts off with a bang? However, she is a great reader (and loves it), is working on finishing up cursive, and is capable of writing well, we just haven't implemented it well yet. She will at least be ready for Singapore 3A by then and R&S 3.
I have looked at the posts comparing the writing between the two programs, but I was hoping for some personal advice.

I actually have most of the Bigger program here. It looks great and I'm sure we'd do well with it, but I don't want to under-challenge her?
My options are:
1. Bigger as is (only 4 days/week)
2. Bigger with Extensions (but, please, can someone tell me exactly what the extensions add to it??)
3. Preparing as is