diff --git a/src/calibre/ebooks/metadata/sources/amazon.py b/src/calibre/ebooks/metadata/sources/amazon.py
index 9460ed7ace..6b30a0cd2e 100644
--- a/src/calibre/ebooks/metadata/sources/amazon.py
+++ b/src/calibre/ebooks/metadata/sources/amazon.py
@@ -41,7 +41,7 @@ class Worker(Thread): # {{{
         try:
             self.get_details()
         except:
-            self.log.error('get_details failed for url: %r'%self.url)
+            self.log.exception('get_details failed for url: %r'%self.url)
 
     def get_details(self):
         try:
@@ -168,7 +168,7 @@ class Worker(Thread): # {{{
             if self.isbn:
                 self.plugin.cache_isbn_to_identifier(self.isbn, self.amazon_id)
             if self.cover_url:
-                self.cache_identifier_to_cover_url(self.amazon_id,
+                self.plugin.cache_identifier_to_cover_url(self.amazon_id,
                         self.cover_url)
 
         self.result_queue.put(mi)
diff --git a/src/calibre/ebooks/metadata/sources/test.py b/src/calibre/ebooks/metadata/sources/test.py
index 032041ef29..62b00851de 100644
--- a/src/calibre/ebooks/metadata/sources/test.py
+++ b/src/calibre/ebooks/metadata/sources/test.py
@@ -10,7 +10,7 @@ __docformat__ = 'restructuredtext en'
 import os, tempfile, time
 from Queue import Queue, Empty
 from threading import Event
-
+from functools import partial
 
 from calibre.customize.ui import metadata_plugins
 from calibre import prints
@@ -90,11 +90,17 @@ def test_identify_plugin(name, tests):
             except Empty:
                 break
 
-        prints('Found', len(results), 'matches:')
+        prints('Found', len(results), 'matches:', end=' ')
+        prints('Smaller relevance means better match')
 
-        for mi in results:
+        results.sort(cmp=partial(plugin.compare_identify_results,
+            title=kwargs.get('title', None), authors=kwargs.get('authors',
+                None), identifiers=kwargs.get('identifiers', {})))
+
+        for i, mi in enumerate(results):
+            prints('*'*30, 'Relevance:', i, '*'*30)
             prints(mi)
-            prints('\n\n')
+            prints('*'*75, '\n\n')
 
         possibles = []
         for mi in results:
@@ -117,6 +123,9 @@ def test_identify_plugin(name, tests):
             prints('Failed to find', plugin.test_fields(possibles[0]))
             raise SystemExit(1)
 
+        if results[0] is not possibles[0]:
+            prints('Most relevant result failed the tests')
+
 
     prints('Average time per query', sum(times)/len(times))