I have a kindle fire and that thing blows. but I'm sure a 5 year old wouldn't notice a difference though.
As for the nexus 7, this thing rocks. I have this, the Fire, and ipad 3. I've been using this the most. For those wondering, its very responsive and smooth. No bloatware. Runs very comparable to an ipad 2-3. I do plenty on my nexus, read books/magazines/emails, videos, stream movies, play app games, and it runs great. The only thing I want that it doesnt have is an SD slot.