I've always allowed updates to 'steep' a bit ( a month minimum for full numericals ie 8-9 and so on, a week for incrementals 10.1 to 10.2, you get the idea) simply to peruse the periodicals for signs of trouble. I think I procrastinated going beyond 10.3.3 about the longest, hearing no positive news about 11, but so many horror stories, last of which being the constant re-boots in 11.1.2 after a certain dste/time....leading to a hasty push of 11.2....Now I can truly say 'I told you so' having hustled to (me????) do 2 iPads & 2 iPhones this morning. All went butter smoothly and we're in fact among the quickest I've done since I've used iOS ( 4S, iOS 5 I believe). I did them OTA ( my iMac seems troublesome after I did High Sierra a month or so ago, so I'm awaiting the customary 'bug fix' in due course before getting serious with it, on it - but all is well in iOS. I will add my humble thoughts to the pile of those who feel Steve Jobs must be rolling in his grave about the quality control issues in Apple software