[ReidZB]

I've had CloudFormation fail to roll back plenty of times, though never in a situation where it actually mattered.

I've never had Terraform "forget" resources or disallow me from deleting them (unless I requested that). Maybe those are bugs that've since been fixed?

It sounds like we've had very different experiences with these tools.

[alexbanks]

My experience with CloudFormation has been consistent with what you just said. CF will fail to delete resources and then lock them in that state, requiring AWS tickets and reps and all that. I have not had anything like that in TF.