Here is a review left by a customer on a product. Would you say he was satisfied or dissatisfied?
Title: fine lense
Review: I haven't as yet used the item but it fits perfectly and the auto focus works fine. The teleconverter only adds a negligible amount of weight and length to the lense which is a 70 to 300 mm. I choose the 1.4x because it doesn't cut the light by as much as a 2x. I believe this teleconverter will work just fine for my needs.
