I really wish my lead guitarist would get one because he uses an Auto Wah and it's never set right eg the opening to Enter Sandman.
Autowah has its place maybe when you are consistently sweeping but for anything else I wouldn't touch it with a bargepole. I don't really like anything like that though tbh I guess it comes to having a classical background and having it driven into me the need to control things very precisely and to strive for the difference between 99.9% and 100%.