diff --git a/src/PureClarity/Api/Feed/Feed.php b/src/PureClarity/Api/Feed/Feed.php
index a06c1bc..6377f0e 100755
--- a/src/PureClarity/Api/Feed/Feed.php
+++ b/src/PureClarity/Api/Feed/Feed.php
@@ -48,8 +48,11 @@ abstract class Feed
     /** @var string[] $nonEmptyFields - Fields that must contain data */
     protected $nonEmptyFields = [];
 
-    /** @var string $pageData - Feed Data */
-    protected $pageData = '';
+    /** @var string[] $pageData - Feed Data buffer */
+    protected $pageData = [];
+
+    /** @var string $itemSeparator - Separator between items in a page */
+    protected $itemSeparator = ',';
 
     /** @var integer $pageSize - Feed Handler class */
     protected $pageSize = 50;
@@ -100,16 +103,17 @@ public function start()
     public function append($data)
     {
         $errors = $this->validate($data);
-        if (empty($errors) === false) {
+        if (!empty($errors)) {
             throw new Exception(implode('|', $errors));
         }
 
         $this->dataIndex++;
-        $this->pageData .= $this->processData($data);
+        $this->pageData[] = $this->processData($data);
 
         if (($this->dataIndex % $this->pageSize) === 0) {
-            $this->transfer->append($this->pageData);
-            $this->pageData = '';
+            $separator = ($this->dataIndex > $this->pageSize) ? $this->itemSeparator : '';
+            $this->transfer->append($separator . implode($this->itemSeparator, $this->pageData));
+            $this->pageData = [];
         }
     }
 
@@ -122,11 +126,6 @@ public function append($data)
     protected function processData($data)
     {
         $data['_index'] = $this->dataIndex;
-
-        if ($this->dataIndex >= 2) {
-            $this->pageData .= ',';
-        }
-
         return json_encode($data);
     }
 
@@ -161,9 +160,10 @@ protected function validate($data)
      */
     public function end()
     {
-        if ($this->pageData !== '') {
-            $this->transfer->append($this->pageData);
-            $this->pageData = '';
+        if (!empty($this->pageData)) {
+            $separator = ($this->dataIndex > $this->pageSize) ? $this->itemSeparator : '';
+            $this->transfer->append($separator . implode($this->itemSeparator, $this->pageData));
+            $this->pageData = [];
         }
 
         $this->transfer->close($this->feedEnd);
diff --git a/src/PureClarity/Api/Feed/Transfer.php b/src/PureClarity/Api/Feed/Transfer.php
index a583c45..b9db396 100755
--- a/src/PureClarity/Api/Feed/Transfer.php
+++ b/src/PureClarity/Api/Feed/Transfer.php
@@ -32,6 +32,9 @@ class Transfer
     /** @var string $feedId */
     private $feedId;
 
+    /** @var string $endpointUrl - Cached SFTP endpoint URL */
+    private $endpointUrl;
+
     /**
      * @param string $feedType - Feed Type, used in naming of the feed file
      * @param string $accessKey - Application Access Key
@@ -133,7 +136,13 @@ private function buildRequest($data)
     private function send($endPoint, $data)
     {
         $request = $this->buildRequest($data);
-        $url = $this->getSftpEndpoint($this->region) . $endPoint;
+        
+        // Cache the endpoint URL on first use
+        if (!$this->endpointUrl) {
+            $this->endpointUrl = $this->getSftpEndpoint($this->region);
+        }
+        
+        $url = $this->endpointUrl . $endPoint;
         $request = http_build_query($request);
 
         $curl = new Curl();
@@ -152,7 +161,7 @@ private function send($endPoint, $data)
             );
         }
 
-        if (empty($error) === false) {
+        if (!empty($error)) {
             throw new Exception($error);
         }
 
diff --git a/src/PureClarity/Api/Feed/Type/Order.php b/src/PureClarity/Api/Feed/Type/Order.php
index eed9e7b..750d70f 100755
--- a/src/PureClarity/Api/Feed/Type/Order.php
+++ b/src/PureClarity/Api/Feed/Type/Order.php
@@ -18,6 +18,9 @@ class Order extends Feed
     /** @var string $feedType */
     protected $feedType = self::FEED_TYPE_ORDER;
 
+    /** @var string $itemSeparator - No separator for CSV format */
+    protected $itemSeparator = '';
+
     /** @var string[] $requiredFields - Fields that must be present in the data (regardless of content) */
     protected $requiredFields = [
         'OrderID',
@@ -53,19 +56,19 @@ class Order extends Feed
      */
     public function processData($orderData)
     {
-        $data = '';
+        $lines = [];
         foreach ($orderData as $orderLine) {
-            $data .= PHP_EOL . $orderLine['OrderID'] . ',' .
-                     $orderLine['UserId'] . ',' .
-                     $orderLine['Email'] . ',' .
-                     $orderLine['DateTime'] . ',' .
-                     $orderLine['ProdCode'] . ',' .
-                     $orderLine['Quantity'] . ',' .
-                     $orderLine['UnitPrice'] . ',' .
-                     $orderLine['LinePrice'];
+            $lines[] = PHP_EOL . $orderLine['OrderID'] . ',' .
+                      $orderLine['UserId'] . ',' .
+                      $orderLine['Email'] . ',' .
+                      $orderLine['DateTime'] . ',' .
+                      $orderLine['ProdCode'] . ',' .
+                      $orderLine['Quantity'] . ',' .
+                      $orderLine['UnitPrice'] . ',' .
+                      $orderLine['LinePrice'];
         }
 
-        return $data;
+        return implode('', $lines);
     }
 
     /**
@@ -78,10 +81,9 @@ protected function validate($orderData)
     {
         $errors = [];
         foreach ($orderData as $orderLine) {
-            $errors = array_merge(
-                $errors,
-                parent::validate($orderLine)
-            );
+            foreach (parent::validate($orderLine) as $error) {
+                $errors[] = $error;
+            }
         }
 
         return $errors;