This is a follow up to my previous entry on the New Tamron Lens. Finally! I received the replacement lens this afternoon and right away I slapped it on my 5d and took it out for a crash test. No “hiccups” and looking through the viewfinder this time was totally crisp with no hint of any dark shadows within the frame as I previously experienced with the other lens. Focusing was smooth and quite responsive and the resulting photos from this test came out absolutely sharp with amazing colors. I’m planning a trip to the mountains this weekend so I will have a chance to really give this new lens a good workout. Will have to come back to this review in about 3 months after I have given this lens a fair field test and some abuse.