The Long Turn

Curious what some of your favorite face/heel turns are for wrestlers who had long been or had major runs as the opposite. Thinking Austins heel run in 01, Taker finally going heel again in 99, Bryan a few years back.

Any that particularly standout as more personal favorite and/or big shocks?

Was just pondering this as lifelong, supremely great babyface Sami Zayn/Generico working as a superb heel is one of the sweet surprises of late.

I hear Hulk Hogan had a pretty good one. 
I’d also nominate Neville turning from high flying babyface to miserable bastard and excelling at both.