ActiveAdmin cheat sheet

Here's a little cheat sheet I put together for using the Rails gem ActiveAdmin.

Some of the defaults the gem generates are a little wonky and can have very negative performance impact when the data grows too large.

One thing I'm curious about from the HN crowd is how large you've scaled with ActiveAdmin, and what you've done when you outgrew it? Homegrown admin interface? Some sort of OLTP -> DataMart migration?