Had an issue a month ago where key would not go in at all. Called mobile locksmith, who picked the dustcover out of the way, put my key in, and ordered a replacement. I took car in for installation of the new cylinder the following weekend; when I returned for pick-up, the locksmith showed me that whomever had replaced the cylinder in the past had installed the plastic shield upside down (I recall the previous owner telling me he had had to have a mobile locksmith come out because the keys were misplaced on the day he was moving; the same guy punched a hole in the seat somehow). I didn't need a new cylinder at all, he just re-installed the shield in the correct orientation. Still cost me $100 labor, because it took the same amount of work as replacing the cylinder. Locksmith said that the dust covers do sometimes fail to retract, and the easiest fix is to just remove the dust-cover, which I would be leery about doing on a convertible. No issues since then.