has anyone ever used these before?

 

theyre known to fail often... get stuck open/shut.

 

A manual one is probably your best bet, three bolts and its either on or off

 

Yeah, they are known to fail as mentioned above.

I ended up getting a manual one. I also had a short pipe made which bolts on where the cap goes and directs the exhaust away from the bottom of the car and slightly to the side.