Did you look at the Lenovo A1 7" tablet
? It has good res at 1024x600 but it's a single core OMAP. Not shabby but not the burner the DS7 is with the tegra 2. The Kindle Fire will also be quicker but it's extremely limited with 8gb of non expandable flash memory. Plus it's not really a fully functional tablet. If she's fine with that, at $200 it's not a bad deal. The A1 seems like a nice option and built like a think pad with a magnesium frame.
I like my DS7, but I would love it if it had 1024x600 res. On the plus side, it does have a full size SD card which I use for cards from my real cameras. Most tabs have microSD which renders my collection of full size SD useless. The DS7 is also running honeycomb now.