I have obviously heard of the slowdown effect the fix for Spectre and Meltdown will have, so I have delayed installing the 10.13.3 update. (Yeah, I know there's a risk—I know.) Has anyone noticed any sort of slowdown as a result of the update? And are there any official measurements? I have a 2013 13" MacBook Air (1.3 GHz Intel Core i5). I also have a Late 2011 MacBook Pro 13" on Sierra, but haven't updated it either since the update came out. Same question for that, I guess.