@WilliamNB@nick@cycling@schizanon@famousringo@ssamulczyk I have never had a front derailleur fail either, but then I run friction & replace the cables reasonably often. When servicing other folks bikes, particularly older & lower end bikes, I get a lot of trouble adjusting worn & poorly engineered indexed front derailleurs.
Just run friction, especially on front derailleurs. Few set up issues & so easy to trim.