It's like handing a job to the new guy.
I use it for snippets. Always double check though and always need to remind it of methods that will and will not work. Often it's just inspiration or for doing lengthy subquery style stuff that takes ages to type out. But even then, 10 mins of battling it when I didn't want to take 5 mins to just manually do it is sadly common.
I do like asking it to optimise and it can't find anything that could be better, though. We're friends then.