such as?
CGAs have other downsides for multihoming, too.
<chair hat off>
I really don't want to start a discussion here about cryptographic strength, but my objection to CGAs in the multi6 context is that they include the /48 prefix in the hash, and that is variable in multi6, which means that the host ID changes when you change prefix. I think that's an unfortunate property because it eliminates some possible tricks in the ID/locator split.
Brian