I'd argue that m3 and c3 instances shouldn't be classified as "previous generation", since the m4 and c4 instances don't have any local ephemeral storage. Given the recent EBS incident in GovCloud, I think it's still pretty reasonable to be skeptical of EBS.

Is this the only source? https://www.reddit.com/r/sysadmin/comments/3yv2db/aws_ebs_vo...