AWS offers burstable EC2 instances, which can provide cost savings for workloads with low CPU utilization and occasional bursts. However, these instances have limitations, such as sharing CPU time with other users, accumulating credits that can be used to burst above the baseline, and incurring additional costs if credits are not enough. Burstable instances are not a good option for Kubernetes workloads due to poor performance and inconsistent results, and instead, using a serverless model like AWS Lambda or a managed Kubernetes autoscaler is more cost-effective and reliable.