将 S3 目录上传到 FTP

我需要一个类，该类获取 S3 上的文件夹并将其所有内容（包括其他文件夹和文件）上传到 FTP 目录。处理这个问题的最佳优化方法是什么？

var client = Amazon.AWSClientFactory.CreateAmazonS3Client();
var request = new ListObjectsRequest()
              .WithBucketName("My.SimpleBucket").WithMarker("MyFolder");
 using (ListObjectsResponse response = client.ListObjects(request))
 {
    // here I can get Key and Size and BucketName of each object, 
    // but to get the stream of each object I gotta
    // do again request for each...
    // and this doesn't sound very right to me