I've been a user and advocate of Canon products since 1995, recommending them many times to camera shoppers, but I'm rapidly losing faith in the quality of their L series lenses. In the past 6 months alone, I've had three Canon L lens failures which so far has cost me over $1200. The first failure was the 24-105mm f/4 L, which had the infamous "err 01" failure, which essentially means a ribbon cable loses connection when the lens is zoomed out. While this has been a common failure with this lens among many photographers, Canon refuses to admit the problem is a manufacturing defect. The second failure was with the 100-400mm f/4.5-5.6 IS L lens, which turned out to be the same problem as with the 24-105. My third failure was with the 85mm f/1.2L II lens, which would hang up at the minimum focus distance while seeking focus. Canon wanted to replace the autofocus assembly and untrasonic motor at a ghastly price. They refused to address the problem of a possible mechanical adjustment or repair, so I sent it to Kurt's Camera Repair in San Diego and they were awesome. They actually repaired it, vice replacing the parts and it works perfectly now. Common sense prevailed. To be fair, I realize these lenses are extremely complex with lots of moving parts, but dealing with Canon's Repair support was very frustrating. Swapping out parts is not a repair. I don't know if others are having problems with their Canon L lenses, but I'm seriously considering switching to the Nikon system. Or, replace the Canon L lenses with the excellent Sigma "Art" series lenses, especially if the produce something to compete with the 85mm f/1.2L. I've already replaced the Canon 24-105L with the Sigma Art 24-105 and so far very satisfied with the results.