Biggest learning after 10 years of programming
At first, they always work.
But then they start showing signs of problems. First small things, then big things and finally showstoppers and I would move back to tried and tested systems.
I see that trend a lot now. And we have very cool toys to play with. Redis, Mongo, Meteor, Firebase, Angular, nodejs etc.
Each new thing is good and I still play with all of them and I still use them in our products. But now, I always plan backups.
'cause I know that they will fail and thats why I program backups in case the new tools fail. I always fall back to the tried and tested. Also, for all our products, the foundation is still tried and tested tools like MySQL, Java, PHP and Apache.