Antonio, I've never had an Oly Pro lens shade fail on me, and I've abused the daylights out of the one for my 40-150 f2.8. I quit using the zoom lens shades because they're only intended to shade the widest angle of the zoom range - 40mm with the 40-150 and 12mm with the 12-40. I haven't had any flare or ghosting issues since I stopped shooting with the hoods.
The only accessory failure was with the 12-40 lens cap. Some Gorilla Glue fixed that problem.