I was looking at purchasing this lens either used or refurbed but was unsure of using the 135 on a crop body with no IS. I assume it would be just fine with ample light, but my wife and I do a great deal of low light wedding photography and if it's at all shaky, it's a no-go.
P.S. I have no fears of purchasing the lens refurbished. I've purchased several Canon products refurbished. When I spoke with a Canon rep in their refurbished department she informed me that they NEVER fix or alter a product before placing it in the refurbished line. She simply mentioned that many of the refurbished items are sent back from Best Buy, B&H, Adorama, etc while within warranty for issues that they could not replicate in their labs. They test them, and if they pass, they end up in a little white box and labeled as refurbished. Many items have never even been opened, but sat on the shelves because they had a dented in corner from shipping. After Canon receives the package back, they take it out, test it, and if it passes, it is now refurbished since it is no longer, "brand new". I hope this clarifies things.