So far, so good except that Tech Tools Pro won't run on it; it's the waiting game until they release a patch to make it Sierra-compliant. My machine's running a little slower since Sierra is more of a processor/memory hog than El Capitan. The slowdown mostly affects Parallel's (v12.x) performance so I may have to tweak its settings to see if I can make the most of the new OS, which I pruned already. I disabled SIRI--I have no need for it, but I did have a little fun with it after having just installed Sierra. When she signed herself on and asked, "What can I do for you today?", I impishly said aloud, "SIRI, shut the f*** up." Her reply? "That wasn't very nice."