You're comparing 4th generation storage to third generation. Unfortunately, the I4i instances are not publically available, despite being announced 4 months ago

You're comparing 4th generation storage to third generation. Unfortunately, the I4i instances are not publically available, despite being announced 4 months ago :-( https://press.aboutamazon.com/news-releases/news-release-details/aws-announces-three-new-amazon-ec2-instances-powered-aws https://press.aboutamazon.com/news-releases/news-release-det... https://aws.amazon.com/ec2/instance-types/i4i/ https://aws.amazon.com/ec2/instance-types/i4i/