They actually work okay. On a 2bbl it's important for them to work perfect as otherwise it will screw the A/F up something awful all the time. I've had problems with them on 2bbls... On a 4bbl I've had very few problems with using them until an electric gets on it.
Seems like someone always does on every one I see.
I see them as a slight step down over an electric in the operation I've had, but working properly they are an upgrade over no choke.